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Wilcox AJ, Snowden JM, Ferguson K, Hutcheon J, Basso O. On the study of fetal growth restriction: time to abandon SGA. Eur J Epidemiol 2024; 39:233-239. [PMID: 38429604 DOI: 10.1007/s10654-024-01098-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2023] [Accepted: 01/07/2024] [Indexed: 03/03/2024]
Affiliation(s)
- Allen J Wilcox
- Epidemiology Branch, National Institute of Environmental Health Sciences, PO Box 12233, Durham, NC, 27709, USA.
- Centre for Fertility and Health, Oslo, Norway.
| | - Jonathan M Snowden
- School of Public Health, Oregon Health & Science University - Portland State University, Portland, OR, USA
- Department of Obstetrics and Gynecology, Oregon Health & Science University, Portland, OR, USA
| | - Kelly Ferguson
- Epidemiology Branch, National Institute of Environmental Health Sciences, PO Box 12233, Durham, NC, 27709, USA
| | - Jennifer Hutcheon
- Department of Obstetrics and Gynaecology, University of British Columbia, Vancouver, Canada
| | - Olga Basso
- Department of Obstetrics and Gynecology, McGill University, Montreal, QC, Canada
- Department of Epidemiology, Biostatistics, and Occupational Health, McGill University, Montreal, QC, 27701, Canada
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Cervera SB, Saeed S, Luu TM, Gorgos A, Beltempo M, Claveau M, Basso O, Lapointe A, Tremblay S, Altit G. Evaluation of the association between patent ductus arteriosus approach and neurodevelopment in extremely preterm infants. J Perinatol 2024; 44:388-395. [PMID: 38278962 DOI: 10.1038/s41372-024-01877-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/02/2023] [Revised: 12/28/2023] [Accepted: 01/05/2024] [Indexed: 01/28/2024]
Abstract
OBJECTIVE Assess if unit-level PDA management correlates with neurodevelopmental impairment (NDI) at 18-24 months corrected postnatal age (CPA) in extremely preterm infants. STUDY DESIGN Retrospective analysis of infants born at <29 weeks (2014-2017) across two units having distinct PDA strategies. Site 1 utilized an echocardiography-based treatment strategy aiming for accelerated closure (control). Site 2 followed a conservative approach. PRIMARY ENDPOINT NDI, characterized by cerebral palsy, any Bayley-III composite score <85, sensorineural/mixed hearing loss, or at least unilateral visual impairment. RESULTS 377 infants were evaluated. PDA treatment rates remained unchanged in Site 1 but eventually reached 0% in Site 2. Comparable rates of any/significant NDI were seen across both sites (any NDI: 38% vs 36%; significant NDI: 13% vs 10% for Site 1 and 2, respectively). After adjustments, NDI rates remained similar. CONCLUSION PDA management strategies in extremely preterm newborns showed no significant impact on neurodevelopment outcomes at 18-24 months CPA.
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Affiliation(s)
- Soledad Belén Cervera
- Division of Neonatology, Department of Paediatrics, Sainte-Justine University Health Center, Montréal, QC, Canada
| | - Sahar Saeed
- Department of Public Health Sciences, Queen's University, Kingston, ON, Canada
| | - Thuy Mai Luu
- Neonatal Follow-Up, Department of Paediatrics, Université de Montréal, Montreal, QC, Canada
| | - Andrea Gorgos
- Neonatal Follow-Up, Department of Pediatrics, McGill University, Montreal, QC, Canada
| | - Marc Beltempo
- Division of Neonatology, Department of Pediatrics, McGill University, Montreal, QC, Canada
| | - Martine Claveau
- Division of Neonatology, Department of Pediatrics, McGill University, Montreal, QC, Canada
| | - Olga Basso
- Department of Epidemiology, Biostatistics, and Occupational Health, McGill University, Montreal, QC, Canada
| | - Anie Lapointe
- Division of Neonatology, Department of Paediatrics, Sainte-Justine University Health Center, Montréal, QC, Canada
| | - Sophie Tremblay
- Division of Neonatology, Department of Paediatrics, Sainte-Justine University Health Center, Montréal, QC, Canada
| | - Gabriel Altit
- Division of Neonatology, Department of Paediatrics, Sainte-Justine University Health Center, Montréal, QC, Canada.
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Basso O, Shapiro GD, Gagnon R, Tamblyn R, Platt RW. Type of infertility and prevalence of congenital malformations. Paediatr Perinat Epidemiol 2024; 38:43-53. [PMID: 37859584 DOI: 10.1111/ppe.13012] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/09/2023] [Revised: 09/17/2023] [Accepted: 09/28/2023] [Indexed: 10/21/2023]
Abstract
BACKGROUND Children conceived with assisted reproductive technologies (ART) or after a long waiting time have a higher prevalence of congenital malformations, but few studies have examined the contribution of type of infertility. OBJECTIVES To quantify the association between causes of infertility and prevalence of malformations. METHODS We compared the prevalence at birth of all and severe malformations diagnosed up to age 2 between 6656 children born in 1996-2017 to parents who had previously been assessed for infertility a an academic fertility clinic ("exposed") and 10,382 children born in the same period to parents with no recent medical history of infertility ("reference"). We estimated prevalence ratios (PR) and prevalence differences (PD), by infertility status, type of treatment (non-ART, ART), and infertility diagnosis, in all children and among singletons. RESULTS Compared with children of parents with no infertility, children of parents with infertility had a higher prevalence of malformations (both definitions), particularly following ART conceptions. After accounting for treatment, ovulatory disorders were associated with a higher prevalence of both all (PR 1.49, 95% confidence interval (CI) 1.15, 1.93; PD 3.8, 95% CI 1.0, 6.6) and severe (PR 1.53, 95% CI 1.02, 2.29; PD 1.8, 95% CI -0.2, 3.7) malformations (the estimates refer to exposed children conceived without treatment). Unexplained and male factor infertility were associated with all and severe malformations, respectively. Estimates among singletons were similar. A diagnosis of ovulatory disorders was associated with all malformations also in analyses restricted to exposed children, regardless of treatment (we did not examine severe malformations, due to limited power). CONCLUSIONS In this study, ovulatory disorders were consistently associated with a higher prevalence of congenital malformations (including severe malformations) among live births, regardless of mode of conception.
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Affiliation(s)
- Olga Basso
- Department of Obstetrics and Gynecology, McGill University, Montreal, Quebec, Canada
- Research Institute of the McGill University Health Center, Montreal, Quebec, Canada
- Department of Epidemiology, Biostatistics, and Occupational Health, McGill University, Montreal, Quebec, Canada
| | - Gabriel D Shapiro
- Research Institute of the McGill University Health Center, Montreal, Quebec, Canada
- Department of Epidemiology, Biostatistics, and Occupational Health, McGill University, Montreal, Quebec, Canada
| | - Robert Gagnon
- Department of Obstetrics and Gynecology, McGill University, Montreal, Quebec, Canada
- Research Institute of the McGill University Health Center, Montreal, Quebec, Canada
| | - Robyn Tamblyn
- Department of Epidemiology, Biostatistics, and Occupational Health, McGill University, Montreal, Quebec, Canada
- Department of Medicine, McGill University, Montreal, Quebec, Canada
| | - Robert W Platt
- Research Institute of the McGill University Health Center, Montreal, Quebec, Canada
- Department of Epidemiology, Biostatistics, and Occupational Health, McGill University, Montreal, Quebec, Canada
- Department of Pediatrics, McGill University, Montreal, Quebec, Canada
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Wilcox AJ, Basso O. Inferring fetal growth restriction as rare, severe, and stable over time. Eur J Epidemiol 2023; 38:455-464. [PMID: 37052754 DOI: 10.1007/s10654-023-00985-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2022] [Accepted: 03/03/2023] [Indexed: 04/14/2023]
Abstract
Reduced birthweight is a marker of pathologies that impair growth and also decrease survival. However, "fetal growth restriction" remains poorly defined. Assuming that birthweight itself has no causal effect on neonatal mortality, we can estimate the features of pathological fetal growth that would be required to produce the observed pattern of weight-specific mortality. Under the simplest possible scenario, we find that at 39-41 weeks, pathological fetal growth restriction affects only about 0.5% of U.S. births, with a neonatal mortality risk up to 220-fold. This surprising concentration of pathology among a tiny subset of babies would account for roughly half of neonatal deaths at term. Moreover, the prevalence of these pathological births appears to have remained relatively stable over recent decades, even as neonatal mortality in the U.S. has declined by 90%. In our model, the decline has been driven by the reduction in baseline mortality (i.e., mortality among babies unaffected by growth pathologies), while the relative risk of death among pathologically grown infants has apparently remained stable. Fetal growth restriction is conventionally regarded as common and preventable. In contrast, our observations suggest that pathological fetal growth is rare and constant over time, perhaps the result of unpreventable stochastic errors in embryonic development. Public health strategies may be more effective by setting aside attempts to increase birthweight, and focusing instead on the discovery and support of factors (unrelated to birthweight) that have produced the striking reductions in neonatal mortality over time.
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Affiliation(s)
- Allen J Wilcox
- Epidemiology Branch, National Institute of Environmental Health Sciences, PO Box 12233, Durham, NC, 27709, USA.
- Centre for Fertility and Health Oslo, Oslo, Norway.
| | - Olga Basso
- Department of Obstetrics and Gynecology, McGill University, Montreal, QC, Canada
- Department of Epidemiology Biostatistics, and Occupational Health, McGill University, Montreal, QC, 27701, Canada
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Smith J, Fell DB, Basso O, Velez M, Dayan N. Fresh Compared With Frozen Embryo Transfer and Risk of Severe Maternal Morbidity: A Study of In Vitro Fertilization Pregnancies in Ontario, Canada. J Obstet Gynaecol Can 2023; 45:202-210. [PMID: 36716961 DOI: 10.1016/j.jogc.2023.01.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2022] [Revised: 01/09/2023] [Accepted: 01/10/2023] [Indexed: 01/29/2023]
Abstract
OBJECTIVES To quantify the risk of severe maternal morbidity (SMM) in fresh versus frozen-thawed embryo transfers (ETs) among pregnancies conceived by in vitro fertilization and to assess SMM risk according to the number of fresh ETs prior to the index pregnancy. METHODS Retrospective cohort study using the provincial birth registry in Ontario, Canada. We included 13 929 individuals aged 18-55 years who conceived via in vitro fertilization between January 1, 2013, and March 5, 2018, and delivered a live or stillborn infant ≥20 weeks gestation. We compared the primary outcome, a composite of SMM or death, between fresh and frozen ETs. RESULTS A total of 174 individuals who conceived via fresh ETs had SMM (30.7 per 1000), compared with 280 among individuals who received frozen ETs (33.9 per 1000); adjusted risk ratio (aRR) 0.85 (95% CI 0.70-1.04). Compared with frozen ET, fresh ET was associated with a lower risk of severe hemorrhage (aRR 0.63; 95% CI 0.48-0.82) but no difference in risk of preeclampsia. Among individuals with 1 (n = 211) or ≥2 (n = 88) prior fresh cycles, the risk of SMM was not increased compared with having no prior cycles; aRR 0.96 (95% CI 0.78-1.18) and 0.91 (95% CI 0.67-1.25), respectively. CONCLUSION Fresh ET was associated with a lower risk of severe hemorrhage compared with frozen ET. These findings may be partly explained by the increased popularity of a freeze-all strategy, reserving fresh ETs for patients with fewer comorbidities.
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Affiliation(s)
- Julia Smith
- Department of Epidemiology, Biostatistics and Occupational Health, McGill University, Montreal, QC; Research Institute, McGill University Health Centre, Montreal, QC
| | - Deshayne B Fell
- School of Epidemiology and Public Health (SEPH), University of Ottawa, Ottawa, ON; Children's Hospital of Eastern Ontario Research Institute, Ottawa, ON
| | - Olga Basso
- Department of Epidemiology, Biostatistics and Occupational Health, McGill University, Montreal, QC; Department of Obstetrics and Gynecology, McGill University Health Centre, Montreal, QC
| | - Maria Velez
- Department of Obstetrics & Gynecology, Queen's University, Kingston, ON
| | - Natalie Dayan
- Department of Epidemiology, Biostatistics and Occupational Health, McGill University, Montreal, QC; Research Institute, McGill University Health Centre, Montreal, QC.
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Basso O, Shapiro GD, Twardowski SE, Monnier P, Buckett W, Tamblyn R. The influence of regulation of medically assisted reproduction on the risk of hospitalization in the first 2 years of life. Hum Reprod 2022; 37:2143-2153. [PMID: 35861659 DOI: 10.1093/humrep/deac158] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2021] [Revised: 06/23/2022] [Indexed: 11/15/2022] Open
Abstract
STUDY QUESTION Do publicly funded fertility treatment and single embryo transfer (SET) result in lower hospitalization rates of children of parents with infertility? SUMMARY ANSWER Following the 2010 Quebec law introducing free fertility treatment and SET, neonatal intensive care unit (NICU) admissions decreased among all children born to parents with infertility, but not among singletons, whose risk remained slightly higher than that of children of parents without infertility, even accounting for treatment and maternal age. WHAT IS KNOWN ALREADY Previous studies reported lower NICU admission rates among children conceived with ART after the 2010 law; however, children conceived without ART by parents with infertility were not considered. STUDY DESIGN, SIZE, DURATION Cohort study of children born in 1997-2017 to patients evaluated for infertility ('exposed') at an academic fertility center in Montreal (Canada) in 1996-2015. A random sample of births to Montreal residents served as comparison. Outcomes were identified from Quebec administrative databases. PARTICIPANTS/MATERIALS, SETTING, METHODS We compared children's healthcare utilization before and after the 2010 law in 6273 exposed and 12 583 randomly sampled births (6846 and 12 775 children, respectively). We repeated the analysis among children conceived in the 63 months before and after the law ('restricted period'), and examined whether differences in twinning, fertility treatment, and maternal age explained the higher risk of NICU admission among children of parents with infertility. MAIN RESULTS AND THE ROLE OF CHANCE In the exposed cohort, the proportion of twin births and of several adverse outcomes declined after the law. NICU admission and duration of NICU stay decreased overall, but not in singletons. Both measures remained higher in exposed children. Except for NICU admission, hospitalization rates were similar in exposed and random sample children. After accounting for fertility treatment and maternal age, exposed singletons were 17% more likely to be admitted to the NICU than children of parents with no medical history of infertility. LIMITATIONS, REASONS FOR CAUTION Sample size was relatively small; infertile patients were from a single center and the random sample from one city. Despite some limitations, administrative databases are likely to accurately reflect healthcare utilization. WIDER IMPLICATIONS OF THE FINDINGS Universal access to treatment and, particularly, SET results in an overall reduction of adverse outcomes among children conceived with treatment; however, children of parents with infertility are at a slightly higher risk, regardless of treatment. STUDY FUNDING/COMPETING INTEREST(S) This study was funded by the Canadian Institutes for Health Research (CIHR, grant no. 123362). No competing interests. TRIAL REGISTRATION NUMBER N/A.
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Affiliation(s)
- Olga Basso
- Department of Obstetrics and Gynecology, McGill University, Montreal, QC, Canada.,Research Institute of the McGill University Health Center, Montreal, QC, Canada.,Department of Epidemiology, Biostatistics, and Occupational Health, McGill University, Montreal, QC, Canada
| | - Gabriel D Shapiro
- Research Institute of the McGill University Health Center, Montreal, QC, Canada.,Department of Epidemiology, Biostatistics, and Occupational Health, McGill University, Montreal, QC, Canada
| | - Sarah E Twardowski
- Department of Epidemiology, Biostatistics, and Occupational Health, McGill University, Montreal, QC, Canada
| | - Patricia Monnier
- Department of Obstetrics and Gynecology, McGill University, Montreal, QC, Canada.,Research Institute of the McGill University Health Center, Montreal, QC, Canada
| | - William Buckett
- Department of Obstetrics and Gynecology, McGill University, Montreal, QC, Canada.,Research Institute of the McGill University Health Center, Montreal, QC, Canada
| | - Robyn Tamblyn
- Department of Epidemiology, Biostatistics, and Occupational Health, McGill University, Montreal, QC, Canada.,Department of Medicine, McGill University, Montreal, QC, Canada.,Clinical and Health Informatics Research Group, McGill University, Montreal, QC, Canada
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Flatman LK, Abrahamowicz M, St-Pierre Y, Malhamé I, Basso O, Bernatsky S, Vinet E. OP0130 SERIOUS INFECTIONS IN OFFSPRING EXPOSED TO TUMOUR NECROSIS FACTOR INHIBITORS DURING PREGNANCY: COMPARISON OF AGENTS WITH LOW AND HIGH PLACENTAL TRANSFER. Ann Rheum Dis 2022. [DOI: 10.1136/annrheumdis-2022-eular.1038] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
BackgroundDuring pregnancy, maternal circulating antibodies cross the placenta. Offspring exposed in utero to tumour necrosis factor inhibitors (TNFi) may experience immunosuppression and subsequent infections in their first year of life due to TNFi entering the fetal bloodstream. TNFi subtypes have differential trans-placental passage capabilities. Most (i.e. adalimumab, infliximab, golimumab) are monoclonal antibodies, with adalimumab and infliximab having the highest transfer, reaching higher fetal than maternal levels. Certolizumab (a pegylated Fab fragment) and etanercept (a fusion protein) display the lowest passage. Thus, depending on the TNFi subtype, the risk of immunosuppression may differ, and some offspring may be exposed to supra-therapeutic doses of TNFi. Therefore, the risk of serious infections in offspring by TNFi subtype needs to be clarified.ObjectivesWe evaluated the risk of serious infections leading to hospitalization in offspring born to mothers with chronic inflammatory diseases who used TNFi during pregnancy depending on whether they had low or high placental transfer.MethodsIn this population cohort study, we identified offspring born in 2011-2019 to women with a prior diagnosis of rheumatoid arthritis, ankylosing spondylitis, psoriatic arthritis, psoriasis, and/or inflammatory bowel diseases in the IBM MarketScan commercial database using commercial claims only. Women were included if they had been continuously enrolled within MarketScan with medical and pharmacy coverage for ≥12 months prior to delivery and had a child linked to them. TNFi exposure was defined as ≥1 filled prescription and/or infusion procedure code during pregnancy. Exposure was further categorized into high (i.e. infliximab, adalimumab, golimumab) and low (i.e. certolizumab, etanercept) placental transfer ability. Serious infections were ascertained based on ≥1 hospitalization with infection as the primary diagnosis in the offspring’s first year of life. We performed multivariable time-to-event analysis using a Cox proportional hazards model, adjusting for maternal age at delivery, chronic inflammatory disease diagnosis, maternal co-morbidities (pre-gestational diabetes, asthma), pregnancy complications (gestational diabetes, preterm birth), and other drug use (corticosteroids and non-biologic DMARDs).ResultsWe identified 26,088 offspring, among whom 2,902 (11.1%) were exposed to TNFi during pregnancy. The majority of offspring (1,506; 51.9%) were born to mothers with inflammatory bowel diseases. Out of the 2,902 offspring with TNFi exposure, 797 (27.5%) and 2,105 (72.5%) were low and high placental transfer drugs, respectively. The frequency of serious infections was 1.3% and 1.8% in those offspring exposed to TNFi with low and high placental transfer, respectively. The incidence rate (IR) of serious infections in offspring exposed to TNFi with high vs. low placental transfer was, respectively, 2.27 (95% confidence interval, CI 1.61, 3.12) cases per 100 person-years at risk vs. IR 1.59 cases per 100 person-years at risk (95% CI 0.76, 2.92). In multivariable analyses, the adjusted hazard ratio for serious infections with the use of TNFi with high versus low placental transfer was 1.20 (95% CI 0.54, 2.64).ConclusionAlthough children exposed to high transfer TNFi may have a higher risk of serious infection, we saw no clear excess risk of serious infections in children exposed in utero to TNFi with high versus low placental transfer due to the wide confidence interval.ReferencesNoneDisclosure of InterestsNone declared
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Dayan N, Velez MP, Vigod S, Pudwell J, Djerboua M, Fell DB, Basso O, Nguyen TV, Joseph KS, Ray JG. Infertility treatment and postpartum mental illness: a population-based cohort study. CMAJ Open 2022; 10:E430-E438. [PMID: 35580889 PMCID: PMC9196066 DOI: 10.9778/cmajo.20210269] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
BACKGROUND Subfertility and infertility treatment can be stressful experiences, but it is unknown whether each predisposes to postpartum mental illness. We sought to evaluate associations between subfertility or infertility treatment and postpartum mental illness. METHODS We conducted a population-based cohort study of individuals without pre-existing mental illness who gave birth in Ontario, Canada, from 2006 to 2014, stratified by fertility exposure: subfertility without infertility treatment; noninvasive infertility treatment (intrauterine insemination); invasive infertility treatment (in vitro fertilization); and no reproductive assistance. The primary outcome was mental illness occurring 365 days or sooner after birth (defined as ≥ 2 outpatient visits, an emergency department visit or a hospital admission with a mood, anxiety, psychotic, or substance use disorder, self-harm event or other mental illness). We used multivariable Poisson regression with robust error variance to assess associations between fertility exposure and postpartum mental illness. RESULTS The study cohort comprised 786 064 births (mean age 30.42 yr, standard deviation 5.30 yr), including 78 283 with subfertility without treatment, 9178 with noninvasive infertility treatment, 9633 with invasive infertility treatment and 688 970 without reproductive assistance. Postpartum mental illness occurred in 60.8 per 1000 births among individuals without reproductive assistance. Relative to individuals without reproductive assistance, those with subfertility had a higher adjusted relative risk of postpartum mental illness (1.14, 95% confidence interval 1.10-1.17), which was similar in noninvasive and invasive infertility treatment groups. INTERPRETATION Subfertility or infertility treatment conferred a slightly higher risk of postpartum mental illness compared with no reproductive assistance. Further research should elucidate whether the stress of infertility, its treatment or physician selection contributes to this association.
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Affiliation(s)
- Natalie Dayan
- Departments of Medicine, and of Obstetrics and Gynaecology (Dayan, Basso, Nguyen), McGill University Health Centre; Research Institute (Dayan, Basso, Nguyen), McGill University Health Centre; Departments of Epidemiology, Biostatistics and Occupational Health (Dayan, Basso), McGill University, Montréal, Que.; Department of Obstetrics and Gynaecology (Velez, Pudwell), Queen's University, Kingston Health Sciences Centre; ICES Queen's (Velez, Djerboua), Kingston, Ont.; ICES Central (Vigod, Ray), Toronto, Ont.; Department of Psychiatry (Vigod), University of Toronto, Toronto, Ont.; ICES uOttawa (Fell); Children's Hospital of Eastern Ontario Research Institute (Fell); School of Epidemiology and Public Health (Fell), University of Ottawa; Better Outcomes Registry & Network (BORN Ontario) (Fell), Ottawa, Ont.; Department of Obstetrics and Gynecology (Joseph), School of Population and Public Health, University of British Columbia, Vancouver, BC; Department of Medicine and Obstetrics and Gynaecology (Ray), University of Toronto, St. Michael's Hospital, Toronto, Ont.
| | - Maria P Velez
- Departments of Medicine, and of Obstetrics and Gynaecology (Dayan, Basso, Nguyen), McGill University Health Centre; Research Institute (Dayan, Basso, Nguyen), McGill University Health Centre; Departments of Epidemiology, Biostatistics and Occupational Health (Dayan, Basso), McGill University, Montréal, Que.; Department of Obstetrics and Gynaecology (Velez, Pudwell), Queen's University, Kingston Health Sciences Centre; ICES Queen's (Velez, Djerboua), Kingston, Ont.; ICES Central (Vigod, Ray), Toronto, Ont.; Department of Psychiatry (Vigod), University of Toronto, Toronto, Ont.; ICES uOttawa (Fell); Children's Hospital of Eastern Ontario Research Institute (Fell); School of Epidemiology and Public Health (Fell), University of Ottawa; Better Outcomes Registry & Network (BORN Ontario) (Fell), Ottawa, Ont.; Department of Obstetrics and Gynecology (Joseph), School of Population and Public Health, University of British Columbia, Vancouver, BC; Department of Medicine and Obstetrics and Gynaecology (Ray), University of Toronto, St. Michael's Hospital, Toronto, Ont
| | - Simone Vigod
- Departments of Medicine, and of Obstetrics and Gynaecology (Dayan, Basso, Nguyen), McGill University Health Centre; Research Institute (Dayan, Basso, Nguyen), McGill University Health Centre; Departments of Epidemiology, Biostatistics and Occupational Health (Dayan, Basso), McGill University, Montréal, Que.; Department of Obstetrics and Gynaecology (Velez, Pudwell), Queen's University, Kingston Health Sciences Centre; ICES Queen's (Velez, Djerboua), Kingston, Ont.; ICES Central (Vigod, Ray), Toronto, Ont.; Department of Psychiatry (Vigod), University of Toronto, Toronto, Ont.; ICES uOttawa (Fell); Children's Hospital of Eastern Ontario Research Institute (Fell); School of Epidemiology and Public Health (Fell), University of Ottawa; Better Outcomes Registry & Network (BORN Ontario) (Fell), Ottawa, Ont.; Department of Obstetrics and Gynecology (Joseph), School of Population and Public Health, University of British Columbia, Vancouver, BC; Department of Medicine and Obstetrics and Gynaecology (Ray), University of Toronto, St. Michael's Hospital, Toronto, Ont
| | - Jessica Pudwell
- Departments of Medicine, and of Obstetrics and Gynaecology (Dayan, Basso, Nguyen), McGill University Health Centre; Research Institute (Dayan, Basso, Nguyen), McGill University Health Centre; Departments of Epidemiology, Biostatistics and Occupational Health (Dayan, Basso), McGill University, Montréal, Que.; Department of Obstetrics and Gynaecology (Velez, Pudwell), Queen's University, Kingston Health Sciences Centre; ICES Queen's (Velez, Djerboua), Kingston, Ont.; ICES Central (Vigod, Ray), Toronto, Ont.; Department of Psychiatry (Vigod), University of Toronto, Toronto, Ont.; ICES uOttawa (Fell); Children's Hospital of Eastern Ontario Research Institute (Fell); School of Epidemiology and Public Health (Fell), University of Ottawa; Better Outcomes Registry & Network (BORN Ontario) (Fell), Ottawa, Ont.; Department of Obstetrics and Gynecology (Joseph), School of Population and Public Health, University of British Columbia, Vancouver, BC; Department of Medicine and Obstetrics and Gynaecology (Ray), University of Toronto, St. Michael's Hospital, Toronto, Ont
| | - Maya Djerboua
- Departments of Medicine, and of Obstetrics and Gynaecology (Dayan, Basso, Nguyen), McGill University Health Centre; Research Institute (Dayan, Basso, Nguyen), McGill University Health Centre; Departments of Epidemiology, Biostatistics and Occupational Health (Dayan, Basso), McGill University, Montréal, Que.; Department of Obstetrics and Gynaecology (Velez, Pudwell), Queen's University, Kingston Health Sciences Centre; ICES Queen's (Velez, Djerboua), Kingston, Ont.; ICES Central (Vigod, Ray), Toronto, Ont.; Department of Psychiatry (Vigod), University of Toronto, Toronto, Ont.; ICES uOttawa (Fell); Children's Hospital of Eastern Ontario Research Institute (Fell); School of Epidemiology and Public Health (Fell), University of Ottawa; Better Outcomes Registry & Network (BORN Ontario) (Fell), Ottawa, Ont.; Department of Obstetrics and Gynecology (Joseph), School of Population and Public Health, University of British Columbia, Vancouver, BC; Department of Medicine and Obstetrics and Gynaecology (Ray), University of Toronto, St. Michael's Hospital, Toronto, Ont
| | - Deshayne B Fell
- Departments of Medicine, and of Obstetrics and Gynaecology (Dayan, Basso, Nguyen), McGill University Health Centre; Research Institute (Dayan, Basso, Nguyen), McGill University Health Centre; Departments of Epidemiology, Biostatistics and Occupational Health (Dayan, Basso), McGill University, Montréal, Que.; Department of Obstetrics and Gynaecology (Velez, Pudwell), Queen's University, Kingston Health Sciences Centre; ICES Queen's (Velez, Djerboua), Kingston, Ont.; ICES Central (Vigod, Ray), Toronto, Ont.; Department of Psychiatry (Vigod), University of Toronto, Toronto, Ont.; ICES uOttawa (Fell); Children's Hospital of Eastern Ontario Research Institute (Fell); School of Epidemiology and Public Health (Fell), University of Ottawa; Better Outcomes Registry & Network (BORN Ontario) (Fell), Ottawa, Ont.; Department of Obstetrics and Gynecology (Joseph), School of Population and Public Health, University of British Columbia, Vancouver, BC; Department of Medicine and Obstetrics and Gynaecology (Ray), University of Toronto, St. Michael's Hospital, Toronto, Ont
| | - Olga Basso
- Departments of Medicine, and of Obstetrics and Gynaecology (Dayan, Basso, Nguyen), McGill University Health Centre; Research Institute (Dayan, Basso, Nguyen), McGill University Health Centre; Departments of Epidemiology, Biostatistics and Occupational Health (Dayan, Basso), McGill University, Montréal, Que.; Department of Obstetrics and Gynaecology (Velez, Pudwell), Queen's University, Kingston Health Sciences Centre; ICES Queen's (Velez, Djerboua), Kingston, Ont.; ICES Central (Vigod, Ray), Toronto, Ont.; Department of Psychiatry (Vigod), University of Toronto, Toronto, Ont.; ICES uOttawa (Fell); Children's Hospital of Eastern Ontario Research Institute (Fell); School of Epidemiology and Public Health (Fell), University of Ottawa; Better Outcomes Registry & Network (BORN Ontario) (Fell), Ottawa, Ont.; Department of Obstetrics and Gynecology (Joseph), School of Population and Public Health, University of British Columbia, Vancouver, BC; Department of Medicine and Obstetrics and Gynaecology (Ray), University of Toronto, St. Michael's Hospital, Toronto, Ont
| | - Tuong Vi Nguyen
- Departments of Medicine, and of Obstetrics and Gynaecology (Dayan, Basso, Nguyen), McGill University Health Centre; Research Institute (Dayan, Basso, Nguyen), McGill University Health Centre; Departments of Epidemiology, Biostatistics and Occupational Health (Dayan, Basso), McGill University, Montréal, Que.; Department of Obstetrics and Gynaecology (Velez, Pudwell), Queen's University, Kingston Health Sciences Centre; ICES Queen's (Velez, Djerboua), Kingston, Ont.; ICES Central (Vigod, Ray), Toronto, Ont.; Department of Psychiatry (Vigod), University of Toronto, Toronto, Ont.; ICES uOttawa (Fell); Children's Hospital of Eastern Ontario Research Institute (Fell); School of Epidemiology and Public Health (Fell), University of Ottawa; Better Outcomes Registry & Network (BORN Ontario) (Fell), Ottawa, Ont.; Department of Obstetrics and Gynecology (Joseph), School of Population and Public Health, University of British Columbia, Vancouver, BC; Department of Medicine and Obstetrics and Gynaecology (Ray), University of Toronto, St. Michael's Hospital, Toronto, Ont
| | - K S Joseph
- Departments of Medicine, and of Obstetrics and Gynaecology (Dayan, Basso, Nguyen), McGill University Health Centre; Research Institute (Dayan, Basso, Nguyen), McGill University Health Centre; Departments of Epidemiology, Biostatistics and Occupational Health (Dayan, Basso), McGill University, Montréal, Que.; Department of Obstetrics and Gynaecology (Velez, Pudwell), Queen's University, Kingston Health Sciences Centre; ICES Queen's (Velez, Djerboua), Kingston, Ont.; ICES Central (Vigod, Ray), Toronto, Ont.; Department of Psychiatry (Vigod), University of Toronto, Toronto, Ont.; ICES uOttawa (Fell); Children's Hospital of Eastern Ontario Research Institute (Fell); School of Epidemiology and Public Health (Fell), University of Ottawa; Better Outcomes Registry & Network (BORN Ontario) (Fell), Ottawa, Ont.; Department of Obstetrics and Gynecology (Joseph), School of Population and Public Health, University of British Columbia, Vancouver, BC; Department of Medicine and Obstetrics and Gynaecology (Ray), University of Toronto, St. Michael's Hospital, Toronto, Ont
| | - Joel G Ray
- Departments of Medicine, and of Obstetrics and Gynaecology (Dayan, Basso, Nguyen), McGill University Health Centre; Research Institute (Dayan, Basso, Nguyen), McGill University Health Centre; Departments of Epidemiology, Biostatistics and Occupational Health (Dayan, Basso), McGill University, Montréal, Que.; Department of Obstetrics and Gynaecology (Velez, Pudwell), Queen's University, Kingston Health Sciences Centre; ICES Queen's (Velez, Djerboua), Kingston, Ont.; ICES Central (Vigod, Ray), Toronto, Ont.; Department of Psychiatry (Vigod), University of Toronto, Toronto, Ont.; ICES uOttawa (Fell); Children's Hospital of Eastern Ontario Research Institute (Fell); School of Epidemiology and Public Health (Fell), University of Ottawa; Better Outcomes Registry & Network (BORN Ontario) (Fell), Ottawa, Ont.; Department of Obstetrics and Gynecology (Joseph), School of Population and Public Health, University of British Columbia, Vancouver, BC; Department of Medicine and Obstetrics and Gynaecology (Ray), University of Toronto, St. Michael's Hospital, Toronto, Ont
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9
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Behlim T, Basso O, Bushnik T, Kramer MS, Kaufman JS, Yang S. Differences in birthweight by maternal and paternal nativity status in Canada. Paediatr Perinat Epidemiol 2022; 36:113-122. [PMID: 34811763 DOI: 10.1111/ppe.12817] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/22/2021] [Revised: 08/25/2021] [Accepted: 08/27/2021] [Indexed: 11/27/2022]
Abstract
BACKGROUND Parental nativity, as well as duration of residence of foreign-born parents in the host country, has been shown to be associated with size at birth. However, most studies have focused on maternal nativity status only and have not accounted for important characteristics of both parents. OBJECTIVE To explore whether maternal and paternal nativity and length of residence (LOR) are independently associated with birthweight for gestational age in a representative sample of infants in Canada. METHODS We compared mean differences in sex- and gestational age-standardised birthweight z-score by nativity status of both parents in a nationally representative sample of 130,532 singleton infants born between May 2004 and May 2006 to mothers residing in Canada. We categorised parental nativity status into four groups (both parents Canada-born, mother only foreign-born, father only foreign-born and both parents foreign-born) and parents' LOR into three (both ≤10 years, only one parent ≤10 years and both >10 years). We estimated mean differences in birthweight z-score and their 95% confidence intervals in linear regression models adjusted for parity, parents' ages, education, ethnicity and marital status of the mother. RESULTS Compared with babies of Canada-born couples, those of two foreign-born parents had on average smaller birthweight z-score, -0.23 (95% CI -0.28, -0.25). However, after adjustment, the mean difference in z-score was -0.02 (95% CI -0.05, 0.00). Infants born to parents who had both resided in Canada for ≤10 years had a unadjusted mean difference in z-score of -0.27 (95% CI -0.29, -0.26), compared infants whose parents were both Canada-born, but the difference became negligible (-0.02, 95% CI -0.04, 0.01) after adjustment. CONCLUSION The birthweight differences by parental nativity or length of residence observed in our study population could be attributed to differences in the distribution of other parental characteristics that affect birthweight.
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Affiliation(s)
- Tarannum Behlim
- Department of Epidemiology, Biostatistics and Occupational Health, Faculty of Medicine, McGill University, Montreal, QC, Canada
| | - Olga Basso
- Department of Epidemiology, Biostatistics and Occupational Health, Faculty of Medicine, McGill University, Montreal, QC, Canada.,Department of Obstetrics and Gynecology, Faculty of Medicine, Montreal, QC, Canada
| | | | - Michael S Kramer
- Department of Epidemiology, Biostatistics and Occupational Health, Faculty of Medicine, McGill University, Montreal, QC, Canada.,Department of Paediatrics, Faculty of Medicine, McGill University, Montreal, QC, Canada
| | - Jay S Kaufman
- Department of Epidemiology, Biostatistics and Occupational Health, Faculty of Medicine, McGill University, Montreal, QC, Canada
| | - Seungmi Yang
- Department of Epidemiology, Biostatistics and Occupational Health, Faculty of Medicine, McGill University, Montreal, QC, Canada
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10
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Arge LA, Håberg SE, Wilcox AJ, Næss Ø, Basso O, Magnus MC. The association between miscarriage and fecundability: the Norwegian Mother, Father and Child Cohort Study. Hum Reprod 2021; 37:322-332. [PMID: 34792121 PMCID: PMC8804331 DOI: 10.1093/humrep/deab252] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2021] [Revised: 10/21/2021] [Indexed: 12/31/2022] Open
Abstract
STUDY QUESTION Is fecundability associated with miscarriage history and future miscarriage risk? SUMMARY ANSWER Prior miscarriage was associated with lower fecundability, and participants with a history of subfertility (time-to-pregnancy (TTP) ≥12 months) were at a higher risk of subsequent miscarriage. WHAT IS KNOWN ALREADY Although miscarriage and low fecundability share common risk factors, prior studies have reported both lower and higher fecundability after miscarriage. STUDY DESIGN, SIZE, DURATION In this study, we examined two related associations: one, between miscarriage history and subsequent fecundability and, two, between fecundability and miscarriage risk in the subsequent pregnancy. The study is based on the Norwegian Mother, Father and Child Cohort Study (MoBa). In addition, the outcome of the pregnancy after the MoBa index pregnancy was obtained by linking information from three national health registries: the Medical Birth Registry of Norway, the Norwegian Patient Registry and the general practice database. PARTICIPANTS/MATERIALS, SETTING, METHODS We examined the association between number of prior miscarriages and fecundability in 48 537 naturally conceived, planned pregnancies in participants with at least one prior pregnancy. We estimated fecundability ratios (FRs) and 95% CIs using proportional probability regression. We further estimated the relative risk (RR) of miscarriage in the subsequent pregnancy as a function of TTP in the MoBa index pregnancy for 7889 pregnancies using log-binomial regression. Multivariable analyses adjusted for maternal age, pre-pregnancy maternal BMI, smoking status, cycle regularity, income level and highest completed or ongoing education. MAIN RESULTS AND THE ROLE OF CHANCE Fecundability decreased as the number of prior miscarriages increased. The adjusted FRs among women with one, two and three or more prior miscarriages were 0.83 (95% CI: 0.80–0.85), 0.79 (95% CI: 0.74–0.83) and 0.74 (95% CI: 0.67–0.82), respectively, compared with women with no prior miscarriages. Compared to women with a TTP of <3 months, the adjusted RR of miscarriage in the subsequent pregnancy was 1.16 (0.99–1.35) with TTP of 3–6 months, 1.18 (0.93–1.49) with TTP of 7–11 months and 1.43 (1.13–1.81) with TTP of 12 or more months. LIMITATIONS, REASONS FOR CAUTION Information on TTP and prior miscarriages was obtained retrospectively, and TTP was self-reported. MoBa is a pregnancy cohort, and findings may not be generalizable to all women. We were unable to examine the effect of changing partners between pregnancies, as well as other paternal factors such as seminal parameters. We also did not know what proportion of our participants had changed partners between their prior pregnancies and the index pregnancy. Furthermore, it is likely that many early miscarriages are not recognized. WIDER IMPLICATIONS OF THE FINDINGS The association between miscarriage and fecundability may reflect a contribution of occult pregnancy losses to TTP, as well as shared underlying causes for reduced fecundability and miscarriage. STUDY FUNDING/COMPETING INTEREST(S) The study was funded by the Research Council of Norway through its Medical Student Research Program funding scheme (project number 271555/F20), its Centres of Excellence funding scheme (project number 262700) and through the project ‘Women's fertility – an essential component of health and well-being’ (project number 320656). M.C.M. has received funding from the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme (grant agreement number 947684). A.J.W. is supported by the Intramural Program of the National Institute of Environmental Health Sciences at the National Institutes of Health, USA. The authors report no competing interests. TRIAL REGISTRATION NUMBER N/A.
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Affiliation(s)
- Lise A Arge
- Centre for Fertility and Health, Norwegian Institute of Public Health, Oslo, Norway.,Department of Community Medicine and Global Health, Institute of Health and Society, University of Oslo, Oslo, Norway
| | - Siri E Håberg
- Centre for Fertility and Health, Norwegian Institute of Public Health, Oslo, Norway
| | - Allen J Wilcox
- Centre for Fertility and Health, Norwegian Institute of Public Health, Oslo, Norway.,Epidemiology Branch, National Institute of Environmental Health Sciences, Durham, NC, USA
| | - Øyvind Næss
- Department of Community Medicine and Global Health, Institute of Health and Society, University of Oslo, Oslo, Norway.,Division for Mental and Physical Health, Norwegian Institute of Public Health, Oslo, Norway
| | - Olga Basso
- Department of Obstetrics and Gynecology, McGill University, Montreal, QC, Canada.,Department of Epidemiology, Biostatistics and Occupational Health, McGill University, Montreal, QC, Canada
| | - Maria C Magnus
- Centre for Fertility and Health, Norwegian Institute of Public Health, Oslo, Norway
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11
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Dayan N, Shapiro GD, Luo J, Guan J, Fell DB, Laskin CA, Basso O, Park AL, Ray JG. Development and internal validation of a model predicting severe maternal morbidity using pre-conception and early pregnancy variables: a population-based study in Ontario, Canada. BMC Pregnancy Childbirth 2021; 21:679. [PMID: 34615477 PMCID: PMC8496026 DOI: 10.1186/s12884-021-04132-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2021] [Accepted: 09/16/2021] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Improvement in the prediction and prevention of severe maternal morbidity (SMM) - a range of life-threatening conditions during pregnancy, at delivery or within 42 days postpartum - is a public health priority. Reduction of SMM at a population level would be facilitated by early identification and prediction. We sought to develop and internally validate a model to predict maternal end-organ injury or death using variables routinely collected during pre-pregnancy and the early pregnancy period. METHODS We performed a population-based cohort study using linked administrative health data in Ontario, Canada, from April 1, 2006 to March 31, 2014. We included women aged 18-60 years with a livebirth or stillbirth, of which one birth was randomly selected per woman. We constructed a clinical prediction model for the primary composite outcome of any maternal end-organ injury or death, arising between 20 weeks' gestation and 42 days after the birth hospital discharge date. Our model included variables collected from 12 months before estimated conception until 19 weeks' gestation. We developed a separate model for parous women to allow for the inclusion of factors from previous pregnancy(ies). RESULTS Of 634,290 women, 1969 experienced the primary composite outcome (3.1 per 1000). Predictive factors in the main model included maternal world region of origin, chronic medical conditions, parity, and obstetrical/perinatal issues - with moderate model discrimination (C-statistic 0.68, 95% CI 0.66-0.69). Among 333,435 parous women, the C-statistic was 0.71 (0.69-0.73) in the model using variables from the current (index) pregnancy as well as pre-pregnancy predictors and variables from any previous pregnancy. CONCLUSIONS A combination of factors ascertained early in pregnancy through a basic medical history help to identify women at risk for severe morbidity, who may benefit from targeted preventive and surveillance strategies including appropriate specialty-based antenatal care pathways. Further refinement and external validation of this model are warranted and can support evidence-based improvements in clinical practice.
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Affiliation(s)
- Natalie Dayan
- Department of Medicine and Research Institute, McGill University Health Centre, 5252 de Maisonneuve West, 2B.40, Montreal, QC, H4A 3S5, Canada. .,Department of Epidemiology, Biostatistics and Occupational Health, McGill University, Purvis Hall, 1020 Pine Ave West, Montreal, QC, H3A 1A2, Canada.
| | - Gabriel D Shapiro
- Department of Medicine and Research Institute, McGill University Health Centre, 5252 de Maisonneuve West, 2B.40, Montreal, QC, H4A 3S5, Canada.,Department of Epidemiology, Biostatistics and Occupational Health, McGill University, Purvis Hall, 1020 Pine Ave West, Montreal, QC, H3A 1A2, Canada
| | - Jin Luo
- ICES, 2075 Bayview Ave, Toronto, ON, M4N 3M5, Canada
| | - Jun Guan
- ICES, 2075 Bayview Ave, Toronto, ON, M4N 3M5, Canada
| | - Deshayne B Fell
- School of Epidemiology and Public Health, Faculty of Medicine, University of Ottawa, Centre for Practice-Changing Research Building, Room L-1154, 401 Smyth Road, Ottawa, ON, K1H 8L1, Canada
| | - Carl A Laskin
- Departments of Medicine and Obstetrics and Gynecology, University of Toronto, 123 Edward St., suite 1200, Toronto, ON, M5G 1E2, Canada.,TRIO Fertility, 655 Bay St, Toronto, ON, M5G 2K4, Canada
| | - Olga Basso
- Department of Epidemiology, Biostatistics and Occupational Health, McGill University, Purvis Hall, 1020 Pine Ave West, Montreal, QC, H3A 1A2, Canada
| | - Alison L Park
- ICES, 2075 Bayview Ave, Toronto, ON, M4N 3M5, Canada
| | - Joel G Ray
- ICES, 2075 Bayview Ave, Toronto, ON, M4N 3M5, Canada.,Departments of Medicine and Obstetrics and Gynecology, University of Toronto, 123 Edward St., suite 1200, Toronto, ON, M5G 1E2, Canada
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12
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Altit G, Saeed S, Beltempo M, Claveau M, Lapointe A, Basso O. Outcomes of Extremely Premature Infants Comparing Patent Ductus Arteriosus Management Approaches. J Pediatr 2021; 235:49-57.e2. [PMID: 33864797 DOI: 10.1016/j.jpeds.2021.04.014] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/27/2020] [Revised: 03/14/2021] [Accepted: 04/08/2021] [Indexed: 12/28/2022]
Abstract
OBJECTIVE To evaluate the change in the proportion of deaths/bronchopulmonary dysplasia (BPD) among premature infants (born <26 and 26-29 weeks of gestational age) following a policy change to a strict nonintervention approach, compared with standard treatment. STUDY DESIGN We examined 1249 infants (341 born <26 weeks of gestational age) at 2 comparable sites. Site 1 (control) continued medical treatment/ligation, and site 2 (exposed) changed to a nonintervention policy in late 2013. Using the difference-in-differences approach, which accounts for time-invariant differences between sites and secular trends, we assessed changes in death or BPD separately among infants born 26-29 weeks and <26 weeks of gestational age in 2 epochs (epoch 1: 2011-2013; epoch 2: 2014-2017). RESULTS Baseline characteristics were similar across sites and epochs. Medical treatment/ligation use remained stable at site 1 but declined progressively to 0% at site 2, indicating adherence to policy. We saw no difference in death/BPD among infants born at 26-29 weeks of gestational age (12%, 95% CI -1% to 24%). However, incidence of death/BPD increased by 31% among infants born <26 weeks of gestational age (95% CI 10%-51%) in site 2, whereas there was no change in outcomes in site 1. The Score for Neonatal Acute Physiology-Version II, used as a control outcome, did not change in either site, suggesting that our findings were not due to changes in patients' severity. CONCLUSIONS Adherence to a strict conservative policy did not impact death or BPD among 26 weeks but was associated with a significant rise in infants born <26 weeks.
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Affiliation(s)
- Gabriel Altit
- Division of Neonatology, McGill University Health Center, Montreal Children's Hospital, Department of Pediatrics, McGill University, Montreal, Quebec, Canada; Department of Epidemiology, Biostatistics and Occupational Health, McGill University, Montreal, Quebec, Canada.
| | - Sahar Saeed
- Department of Epidemiology, Washington University, St. Louis, MO
| | - Marc Beltempo
- Division of Neonatology, McGill University Health Center, Montreal Children's Hospital, Department of Pediatrics, McGill University, Montreal, Quebec, Canada
| | - Martine Claveau
- Division of Neonatology, McGill University Health Center, Montreal Children's Hospital, Department of Pediatrics, McGill University, Montreal, Quebec, Canada; Ingram School of Nursing, McGill University, Montreal, Quebec, Canada
| | - Anie Lapointe
- Department of Neonatology, CHU Sainte-Justine, Université de Montréal, Montreal, Quebec, Canada
| | - Olga Basso
- Department of Epidemiology, Biostatistics and Occupational Health, McGill University, Montreal, Quebec, Canada; Department of Obstetrics and Gynecology, McGill University Health Center; Montreal, Quebec, Canada
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13
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Basso O, Willis SK, Hatch EE, Mikkelsen EM, Rothman KJ, Wise LA. Maternal age at birth and daughter's fecundability. Hum Reprod 2021; 36:1970-1980. [PMID: 33860312 PMCID: PMC8213449 DOI: 10.1093/humrep/deab057] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2020] [Revised: 02/12/2021] [Indexed: 01/10/2023] Open
Abstract
STUDY QUESTION Do daughters of older mothers have lower fecundability? SUMMARY ANSWER In this cohort study of North American pregnancy planners, there was virtually no association between maternal age ≥35 years and daughters' fecundability. WHAT IS KNOWN ALREADY Despite suggestive evidence that daughters of older mothers may have lower fertility, only three retrospective studies have examined the association between maternal age and daughter's fecundability. STUDY DESIGN, SIZE, DURATION Prospective cohort study of 6689 pregnancy planners enrolled between March 2016 and January 2020. PARTICIPANTS/MATERIALS, SETTING, METHODS Pregnancy Study Online (PRESTO) is an ongoing pre-conception cohort study of pregnancy planners (age, 21-45 years) from the USA and Canada. We estimated fecundability ratios (FR) for maternal age at the participant's birth using multivariable proportional probabilities regression models. MAIN RESULTS AND THE ROLE OF CHANCE Daughters of mothers ≥30 years were less likely to have previous pregnancies (or pregnancy attempts) or risk factors for infertility, although they were more likely to report that their mother had experienced problems conceiving. The proportion of participants with prior unplanned pregnancies, a birth before age 21, ≥3 cycles of attempt at study entry or no follow-up was greater among daughters of mothers <25 years. Compared with maternal age 25-29 years, FRs (95% CI) for maternal age <20, 20-24, 30-34, and ≥35 were 0.72 (0.61, 0.84), 0.92 (0.85, 1.00), 1.08 (1.00, 1.17), and 1.00 (0.89, 1.12), respectively. LIMITATIONS, REASONS FOR CAUTION Although the examined covariates did not meaningfully affect the associations, we had limited information on the participants' mother. Differences by maternal age in reproductive history, infertility risk factors and loss to follow-up suggest that selection bias may partly explain our results. WIDER IMPLICATIONS OF THE FINDINGS Our finding that maternal age 35 years or older was not associated with daughter's fecundability is reassuring, considering the trend towards delayed childbirth. However, having been born to a young mother may be a marker of low fecundability among pregnancy planners. STUDY FUNDING/COMPETING INTEREST(S) PRESTO was funded by NICHD Grants (R21-HD072326 and R01-HD086742) and has received in-kind donations from Swiss Precision Diagnostics, FertilityFriend.com, Kindara.com, and Sandstone Diagnostics. Dr Wise is a fibroid consultant for AbbVie, Inc. TRIAL REGISTRATION NUMBER n/a.
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Affiliation(s)
- Olga Basso
- Department of Obstetrics and Gynecology, Royal Victoria Hospital, Research Institute of McGill University Health Centre, Montreal, QC H3A 1A2, Canada
- Department of Epidemiology, Biostatistics, and Occupational Health, McGill University, Montreal, QC, Canada
| | - Sydney K Willis
- Department of Epidemiology, Boston University School of Public Health, Boston, MA, USA
| | - Elizabeth E Hatch
- Department of Epidemiology, Boston University School of Public Health, Boston, MA, USA
| | - Ellen M Mikkelsen
- Department of Clinical Epidemiology, Department of Clinical Medicine, Aarhus University and Aarhus University Hospital, Aarhus, Denmark
| | - Kenneth J Rothman
- Department of Epidemiology, Boston University School of Public Health, Boston, MA, USA
- Research Triangle Institute, Research Triangle Park, NC, USA
| | - Lauren A Wise
- Department of Epidemiology, Boston University School of Public Health, Boston, MA, USA
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14
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Plana-Ripoll O, Basso O, László KD, Olsen J, Parner E, Cnattingius S, Obel C, Li J. Reproduction after the loss of a child: a population-based matched cohort study. Hum Reprod 2020; 33:1557-1565. [PMID: 30010921 DOI: 10.1093/humrep/dey233] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2018] [Revised: 06/01/2018] [Accepted: 06/11/2018] [Indexed: 11/13/2022] Open
Abstract
STUDY QUESTION Is the death of a child associated with higher subsequent fertility? SUMMARY ANSWER Women who had lost a child had higher fertility both shortly after the loss and throughout the entire follow-up, independent of the child's age at the time of death. WHAT IS KNOWN ALREADY Women who lose a child in the perinatal period often have another child shortly after. However, to our knowledge no previous study has investigated if the death of an older child affects reproductive behavior. STUDY DESIGN, SIZE, DURATION The source population for this matched cohort study consisted of all women who gave birth in Denmark from 1978 to 2004 and in Sweden from 1973 to 2002 (N = 1 979 958). Women were followed through to the end of 2008 in Denmark and the end of 2006 in Sweden. PARTICIPANTS/MATERIALS, SETTING, METHODS Women who had lost a child before the age of 45 years during the study period (exposed group; n = 36 511) were matched with up to five women who were from the same country and of similar age and family characteristics and had not lost a child at the time of matching (unexposed group; n = 182 522). MAIN RESULTS AND THE ROLE OF CHANCE During follow-up, 74% of exposed and 46% of unexposed women had another birth (live- or stillbirth) after a gestation of 28 weeks or more. Compared with unexposed women, exposed women had a shorter interpregnancy interval and, consequently, a higher rate of conception leading to a birth (HR = 5.5 [95% CI: 5.4-5.6]). Rates for exposed women were higher from the first month following the child's death, but the largest difference was between 2 and 3 months after the event. This pattern was independent of the age of the deceased child. Exposed women had more subsequent children than unexposed, leading to a comparable number of living children at the end of follow-up. LIMITATIONS, REASONS FOR CAUTION The use of population-based registers allows for the inclusion of virtually all eligible women and nearly complete follow-up; the potential for selection bias is thus negligible. However, only pregnancies that led to a live birth or a stillbirth could be identified, thus fetal losses occurring before week 28 of gestation were missing. WIDER IMPLICATIONS OF THE FINDINGS Our findings corroborate the previous evidence suggesting that women try to conceive again shortly after a perinatal death, and many succeed. In addition, this is the first study to investigate the reproductive trajectory after losing an older child. The current study indicates that most women who lose a child between the ages of 6 months and 5 years conceive shortly after the loss, and they have a comparable number of living children at the end of the follow-up compared to those who do not lose a child. STUDY FUNDING/COMPETING INTEREST(S) This work was supported by Grant ERC-2010-StG-260242 from the European Research Council, 176673 and 186200 from the Nordic Cancer Union, DFF-6110-00019 from the Danish Council for Independent Research, 904414 and 15199 from TrygFonden, Karen Elise Jensens Fond (2016), and the Program for Clinical Research Infrastructure (PROCRIN) established by the Lundbeck Foundation and the Novo Nordisk Foundation. The authors do not declare any conflicts of interests. TRIAL REGISTRATION NUMBER N/A.
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Affiliation(s)
- O Plana-Ripoll
- National Center for Register-based Research, Aarhus University, Fuglesangs allé 26, Aarhus V, Denmark
| | - O Basso
- Department of Obstetrics and Gynecology, McGill University Health Centre, Royal Victoria Hospital, Glen Site, 1001 Decarie Blvd, Montreal, QC, Canada.,Department of Epidemiology, Biostatistics and Occupational Health, McGill University, 1020 Pine Avenue West, Montreal, QC, Canada
| | - K D László
- Department of Public Health Sciences, Karolinska Institutet, Tomtebodavägen 18A, pl. 3, Stockholm, Sweden
| | - J Olsen
- Department of Clinical Epidemiology, Aarhus University Hospital, Olof Palmes Allé 43-45, Aarhus N, Denmark.,Department of Epidemiology, Fielding School of Public Health, University of California, 650 Charles E. Young Dr. South, Center for Health Sciences, Los Angeles, CA, USA
| | - E Parner
- Section of Biostatistics, Department of Public Health, Aarhus University, Bartholins Allé 2, Aarhus, Denmark
| | - S Cnattingius
- Clinical Epidemiology Unit, Department of Medicine Solna, Karolinska Institutet and Karolinska University Hospital, Stockholm, Sweden
| | - C Obel
- Section of General Practice, Department of Public Health, Aarhus University, Bartholins Allé 2, Aarhus C, Denmark
| | - J Li
- Department of Clinical Epidemiology, Aarhus University Hospital, Olof Palmes Allé 43-45, Aarhus N, Denmark
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15
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Gilbert L, Ramanakumar AV, Festa MC, Jardon K, Zeng X, Martins C, Shbat L, Alsoud MA, Borod M, Wolfson M, Papaioannou I, Basso O, Sampalis J. Real-world direct healthcare costs of treating recurrent high-grade serous ovarian cancer with cytotoxic chemotherapy. J Comp Eff Res 2020; 9:537-551. [PMID: 32223298 DOI: 10.2217/cer-2020-0032] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Aim: To describe the direct healthcare costs associated with repeated cytotoxic chemotherapy treatments for recurrent high-grade serous cancer (HGSC) of the ovaries. Patients & methods: Retrospective review of 66 women with recurrent stage III/IV HGSC ovarian cancer treated with repeated lines of cytotoxic chemotherapy in a Canadian University Tertiary Center. Results: Mean cost of treatment of first relapse was CAD$52,227 increasing by 38% for two, and 86% for three or more relapses with median overall survival of 36.0, 50.7 and 42.8 months, respectively. In-hospital care accounted for 71% and chemotherapy drugs accounted for 17% of the total costs. Conclusion: After the third relapse of HGSC, cytotoxic chemotherapy did not prolong survival but was associated with substantially increased healthcare costs.
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Affiliation(s)
- Lucy Gilbert
- McGill University Health Center, Gynecologic Cancer Services, Cancer Care Mission, 1001 Decarie Boulevard, Montreal, QC, H4A 3J1, Canada.,McGill University, Department of Obstetrics & Gynecology, 1001 Decarie Boulevard, Montreal, QC, H4A 3 J1, Canada.,Department of Oncology, McGill University, 5100 de Maisonneuve Boulevard West, Montreal, QC, H4A 3T2, Canada
| | - Agnihotram V Ramanakumar
- Research Institute of The McGill University Health Center, 1001 Decarie Boulevard, Montreal, QC, H4A 3J1, Canada
| | - Maria Carolina Festa
- McGill University Health Center, Gynecologic Cancer Services, Cancer Care Mission, 1001 Decarie Boulevard, Montreal, QC, H4A 3J1, Canada.,McGill University, Department of Obstetrics & Gynecology, 1001 Decarie Boulevard, Montreal, QC, H4A 3 J1, Canada
| | - Kris Jardon
- McGill University Health Center, Gynecologic Cancer Services, Cancer Care Mission, 1001 Decarie Boulevard, Montreal, QC, H4A 3J1, Canada.,McGill University, Department of Obstetrics & Gynecology, 1001 Decarie Boulevard, Montreal, QC, H4A 3 J1, Canada.,Department of Oncology, McGill University, 5100 de Maisonneuve Boulevard West, Montreal, QC, H4A 3T2, Canada
| | - Xing Zeng
- McGill University Health Center, Gynecologic Cancer Services, Cancer Care Mission, 1001 Decarie Boulevard, Montreal, QC, H4A 3J1, Canada.,McGill University, Department of Obstetrics & Gynecology, 1001 Decarie Boulevard, Montreal, QC, H4A 3 J1, Canada.,Department of Oncology, McGill University, 5100 de Maisonneuve Boulevard West, Montreal, QC, H4A 3T2, Canada
| | - Claudia Martins
- McGill University Health Center, Gynecologic Cancer Services, Cancer Care Mission, 1001 Decarie Boulevard, Montreal, QC, H4A 3J1, Canada.,McGill University, Department of Obstetrics & Gynecology, 1001 Decarie Boulevard, Montreal, QC, H4A 3 J1, Canada.,Department of Oncology, McGill University, 5100 de Maisonneuve Boulevard West, Montreal, QC, H4A 3T2, Canada
| | - Layla Shbat
- McGill University Health Center, Gynecologic Cancer Services, Cancer Care Mission, 1001 Decarie Boulevard, Montreal, QC, H4A 3J1, Canada.,McGill University, Department of Obstetrics & Gynecology, 1001 Decarie Boulevard, Montreal, QC, H4A 3 J1, Canada
| | - Marwa Abo Alsoud
- McGill University Health Center, Gynecologic Cancer Services, Cancer Care Mission, 1001 Decarie Boulevard, Montreal, QC, H4A 3J1, Canada.,McGill University, Department of Obstetrics & Gynecology, 1001 Decarie Boulevard, Montreal, QC, H4A 3 J1, Canada
| | - Manuel Borod
- Department of Oncology, McGill University, 5100 de Maisonneuve Boulevard West, Montreal, QC, H4A 3T2, Canada.,McGill University Health Center, Supportive & Palliative Care Services, Cancer Care Mission, 1001 Decarie Boulevard, Montreal, QC, H4A 3 J1, Canada
| | - Michael Wolfson
- University of Ottawa, Department of Epidemiology & Community Medicine, 600 Peter Morand Crescent, Ottawa, Canada, K1G 5Z3, Canada
| | - Ioanna Papaioannou
- JSS Medical Research, 9400 Henri-Bourassa West, Montreal, QC, H4S 1N8, Canada
| | - Olga Basso
- Research Institute of The McGill University Health Center, 1001 Decarie Boulevard, Montreal, QC, H4A 3J1, Canada.,Department of Epidemiology, Biostatistics, & Occupational Health, McGill University, 1020 Pine Avenue West, Montreal, QC, H3A 1A2, Canada
| | - John Sampalis
- JSS Medical Research, 9400 Henri-Bourassa West, Montreal, QC, H4S 1N8, Canada.,McGill University, Faculty of Medicine, Department of Surgery, Division of Surgical Research, 1650 Cedar Avenue, Montreal, QC, H3G 1A4, Canada
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16
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Basso O. The fragile foundations of the extended fetuses-at-risk approach. Paediatr Perinat Epidemiol 2020; 34:80-85. [PMID: 31960472 DOI: 10.1111/ppe.12607] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/22/2019] [Revised: 10/01/2019] [Accepted: 10/06/2019] [Indexed: 11/27/2022]
Abstract
BACKGROUND Whether denominators for postnatal outcomes (ascertained after live birth) with a presumed prenatal origin should consist of fetuses or live births remains controversial. Proponents argue that the extended fetuses-at-risk (FAR) approach (a), provides a justification for medically indicated preterm delivery, (b), avoids paradoxical results, and (c), permits quantification of incidence of fetal-infant phenomena, such as "revealed" small for gestational age (SGA)-which, under FAR, rises with advancing gestation. METHODS This conceptual paper examines the validity of the above arguments. RESULTS As obstetricians induce babies early because of fetal (or maternal) compromise and despite the dangers posed by immaturity, there is no need to modify a paradigm that portrays preterm birth as a powerful risk factor. The FAR approach generally avoids "paradoxical" intersections because FAR rates of postnatal outcomes depend on the birth rate. However, this property, which causes rates of most postnatal outcomes to rise at term, can also lead to risk reversals and other misleading findings. The FAR formulation does not yield the incidence of postnatal conditions but, rather, the incidence of live birth (and survival to diagnosis) of babies with prevalent conditions (and, sometimes, future ones). CONCLUSIONS The proposed arguments do not provide adequate support for extending the FAR approach to postnatal outcomes. As only live births can contribute to the numerator of rates, the usefulness and interpretability of FAR measures in this setting are limited.
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Affiliation(s)
- Olga Basso
- Department of Obstetrics and Gynecology, Royal Victoria Hospital, Research Institute of McGill University Health Centre, Montreal, QC, Canada.,Department of Epidemiology, Biostatistics, and Occupational Health, McGill University, Montreal, QC, Canada
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17
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Gagliardi L, Basso O. Maternal hypertension and survival in singletons and twins born at 23-29 weeks: not just one answer…. Pediatr Res 2019; 85:697-702. [PMID: 30763949 DOI: 10.1038/s41390-019-0337-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/26/2018] [Revised: 01/17/2019] [Accepted: 02/05/2019] [Indexed: 11/09/2022]
Abstract
BACKGROUND To describe the association between maternal hypertension (chronic and gestational, MH) and mortality in very preterm singletons and twins, focusing on how estimates depend on gestational age (GA) and size at birth. METHODS We estimated relative risks of in-hospital death in 12,320 singletons (MH: 22.4%) and 4381 twins (MH: 10.6%) born at 23-29 weeks in the Italian Neonatal Network (89 hospitals, 2008-2016). RESULTS Babies with MH had higher GA and were more frequently small-for-gestational age (SGA), especially singletons. In crude analyses, MH was associated with lower mortality in singletons. In multivariable analyses, the effects of GA and size differed between twins and singletons with and without MH. The best-fitting models included continuous birth weight (rather than SGA) and were stratified by GA. In these models, MH was associated with lower mortality in singletons-but not twins-born after week 25. CONCLUSIONS In this cohort of very preterm infants, the association between MH and mortality differed between singletons and twins and across strata of GA at birth. These estimates cannot be interpreted causally, but suggest that, from a descriptive/predictive standpoint, singletons with MH born after week 25 have lower mortality than singletons born to women without MH.
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Affiliation(s)
- Luigi Gagliardi
- Department of Woman and Child Health, Pediatrics and Neonatology Division, Ospedale Versilia, Viareggio, AUSL Toscana Nord Ovest, Pisa, Italy.
| | - Olga Basso
- Department of Obstetrics and Gynecology, McGill University Health Centre, Montreal, QC, Canada.,Department of Epidemiology, Biostatistics, and Occ. Health, McGill University, Montreal, QC, Canada
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18
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Affiliation(s)
- Olga Basso
- Department of Obstetrics and Gynecology, McGill University, Montreal, Quebec, Canada
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19
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Basso O, Weinberg CR, D’Aloisio AA, Sandler DP. Mother's age at delivery and daughters' risk of preeclampsia. Paediatr Perinat Epidemiol 2019; 33:129-136. [PMID: 30663124 PMCID: PMC6438740 DOI: 10.1111/ppe.12532] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/11/2018] [Revised: 11/25/2018] [Accepted: 11/27/2018] [Indexed: 12/17/2022]
Abstract
BACKGROUND Some cardiovascular disease risk factors are associated with both risk of preeclampsia and having been born to a younger or older mother. We examined whether mother's age at delivery predicts a primiparous daughter's risk of preeclampsia. METHODS The analysis included 39 803 Sister Study participants (designated as "daughters") born between 1930 and 1974. Using log-binomial regression, we estimated relative risks (RR) of preeclampsia in the first pregnancy ending in birth ("primiparous preeclampsia") associated with mother's age at the daughter's birth. Models included: number of older full and maternal half-siblings, income level growing up, daughter's age at delivery, race/ethnicity, and 5-year birth cohort. We examined self-reported relative weight at age 10 (heavier than peers versus not) as a potential effect measure modifier. RESULTS Overall, 6.2% of daughters reported preeclampsia. Compared with those who had been born to 20-24-year old mothers, daughters of teenage mothers had a relative risk of 1.20 (95% confidence interval (CI) 1.01, 1.43) and daughters of mothers ≥25 had a ~10% lower risk. Relative weight at age 10 modified the association, with an inverse association between mother's age at delivery and preeclampsia seen only among daughters with low/normal childhood relative weight. In this subset, results were consistent across strata of daughter's age at menarche and age at first birth. CONCLUSIONS These findings, based on self-reported data, require replication. Nevertheless, as women increasingly delay childbearing, they provide some reassurance that having been born to an older mother is not, per se, a risk factor for primiparous preeclampsia.
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Affiliation(s)
- Olga Basso
- Dept. of Obstetrics and Gynecology, Royal Victoria Hospital, Research Institute of McGill University Health Centre, Montreal, Canada, H4A 3J1
- Dept. of Epidemiology, Biostatistics, and Occupational Health, McGill University
| | - Clarice R Weinberg
- Biostatistics and Computational Biology Branch, National Institute of Environmental Health Sciences, NIH, Research Triangle Park, USA, 27709
| | | | - Dale P Sandler
- Epidemiology Branch, National Institute of Environmental Health Sciences, NIH, Research Triangle Park, USA, 27709
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20
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Dayan N, Joseph KS, Fell DB, Laskin CA, Basso O, Park AL, Luo J, Guan J, Ray JG. Infertility treatment and risk of severe maternal morbidity: a propensity score-matched cohort study. CMAJ 2019; 191:E118-E127. [PMID: 30718336 PMCID: PMC6351248 DOI: 10.1503/cmaj.181124] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/19/2018] [Indexed: 11/01/2022] Open
Abstract
BACKGROUND The extent to which infertility treatment predicts severe maternal morbidity is not well known. We examined the association between infertility treatment and severe maternal morbidity in pregnancy and the postpartum period. METHODS We conducted a cohort study using population-based registries from Ontario between 2006 and 2012. Pregnancies achieved using infertility treatment (ovulation induction, intrauterine insemination or in vitro fertilization with or without intracytoplasmic sperm injection) were compared with unassisted pregnancies using propensity score matching, based on demographic, reproductive and obstetric factors. The primary outcome was a validated composite of severe maternal morbidity or maternal death from 20 weeks' gestation to 42 days postpartum. We also calculated the odds ratio of a woman having 1, 2, or 3 or more severe maternal morbidity indicators in relation to invasive (e.g., in vitro fertilization) or noninvasive (e.g., intrauterine insemination) infertility treatment. RESULTS We matched 11 546 infertility treatment pregnancies with 47 553 untreated pregnancies. Severe maternal morbidity or maternal death occurred in 356 infertility-treated pregnancies (30.8 per 1000 deliveries) versus 1054 untreated pregnancies (22.2 per 1000 deliveries); relative risk 1.39 (95% confidence interval [CI] 1.23-1.56). The likelihood of a woman having 3 or more severe maternal morbidity indicators was increased in women who received invasive infertility treatment (odds ratio [OR] 2.28, 95% CI 1.56-3.33) but not in those who received noninvasive infertility treatment (OR 0.99, 95% CI 0.57-1.72). INTERPRETATION Women who undergo infertility treatment, particularly in vitro fertilization, are at somewhat higher risk of severe maternal morbidity or death. Efforts are needed to identify patient- and treatment-specific predictors of severe maternal morbidity that may influence the type of treatment a woman is offered.
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Affiliation(s)
- Natalie Dayan
- Department of Medicine and Research Institute (Dayan), Department of Obstetrics and Gynecology (Basso), McGill University Health Centre; Department of Epidemiology, Biostatistics and Occupational Health (Dayan, Basso), McGill University, Montréal, Que.; Department of Obstetrics and Gynaecology, and School of Population and Public Health (Joseph), University of British Columbia, Vancouver, BC; Children's Hospital of Eastern Ontario Research Institute (Fell); School of Epidemiology and Public Health (Fell), University of Ottawa, Ottawa, Ont.; Department of Medicine and Obstetrics and Gynecology (Laskin), University of Toronto; TRIO Fertility (Laskin); ICES (Park, Luo, Guan, Ray, Fell); Department of Medicine (Ray), St. Michael's Hospital, Toronto, Ont.
| | - K S Joseph
- Department of Medicine and Research Institute (Dayan), Department of Obstetrics and Gynecology (Basso), McGill University Health Centre; Department of Epidemiology, Biostatistics and Occupational Health (Dayan, Basso), McGill University, Montréal, Que.; Department of Obstetrics and Gynaecology, and School of Population and Public Health (Joseph), University of British Columbia, Vancouver, BC; Children's Hospital of Eastern Ontario Research Institute (Fell); School of Epidemiology and Public Health (Fell), University of Ottawa, Ottawa, Ont.; Department of Medicine and Obstetrics and Gynecology (Laskin), University of Toronto; TRIO Fertility (Laskin); ICES (Park, Luo, Guan, Ray, Fell); Department of Medicine (Ray), St. Michael's Hospital, Toronto, Ont
| | - Deshayne B Fell
- Department of Medicine and Research Institute (Dayan), Department of Obstetrics and Gynecology (Basso), McGill University Health Centre; Department of Epidemiology, Biostatistics and Occupational Health (Dayan, Basso), McGill University, Montréal, Que.; Department of Obstetrics and Gynaecology, and School of Population and Public Health (Joseph), University of British Columbia, Vancouver, BC; Children's Hospital of Eastern Ontario Research Institute (Fell); School of Epidemiology and Public Health (Fell), University of Ottawa, Ottawa, Ont.; Department of Medicine and Obstetrics and Gynecology (Laskin), University of Toronto; TRIO Fertility (Laskin); ICES (Park, Luo, Guan, Ray, Fell); Department of Medicine (Ray), St. Michael's Hospital, Toronto, Ont
| | - Carl A Laskin
- Department of Medicine and Research Institute (Dayan), Department of Obstetrics and Gynecology (Basso), McGill University Health Centre; Department of Epidemiology, Biostatistics and Occupational Health (Dayan, Basso), McGill University, Montréal, Que.; Department of Obstetrics and Gynaecology, and School of Population and Public Health (Joseph), University of British Columbia, Vancouver, BC; Children's Hospital of Eastern Ontario Research Institute (Fell); School of Epidemiology and Public Health (Fell), University of Ottawa, Ottawa, Ont.; Department of Medicine and Obstetrics and Gynecology (Laskin), University of Toronto; TRIO Fertility (Laskin); ICES (Park, Luo, Guan, Ray, Fell); Department of Medicine (Ray), St. Michael's Hospital, Toronto, Ont
| | - Olga Basso
- Department of Medicine and Research Institute (Dayan), Department of Obstetrics and Gynecology (Basso), McGill University Health Centre; Department of Epidemiology, Biostatistics and Occupational Health (Dayan, Basso), McGill University, Montréal, Que.; Department of Obstetrics and Gynaecology, and School of Population and Public Health (Joseph), University of British Columbia, Vancouver, BC; Children's Hospital of Eastern Ontario Research Institute (Fell); School of Epidemiology and Public Health (Fell), University of Ottawa, Ottawa, Ont.; Department of Medicine and Obstetrics and Gynecology (Laskin), University of Toronto; TRIO Fertility (Laskin); ICES (Park, Luo, Guan, Ray, Fell); Department of Medicine (Ray), St. Michael's Hospital, Toronto, Ont
| | - Alison L Park
- Department of Medicine and Research Institute (Dayan), Department of Obstetrics and Gynecology (Basso), McGill University Health Centre; Department of Epidemiology, Biostatistics and Occupational Health (Dayan, Basso), McGill University, Montréal, Que.; Department of Obstetrics and Gynaecology, and School of Population and Public Health (Joseph), University of British Columbia, Vancouver, BC; Children's Hospital of Eastern Ontario Research Institute (Fell); School of Epidemiology and Public Health (Fell), University of Ottawa, Ottawa, Ont.; Department of Medicine and Obstetrics and Gynecology (Laskin), University of Toronto; TRIO Fertility (Laskin); ICES (Park, Luo, Guan, Ray, Fell); Department of Medicine (Ray), St. Michael's Hospital, Toronto, Ont
| | - Jin Luo
- Department of Medicine and Research Institute (Dayan), Department of Obstetrics and Gynecology (Basso), McGill University Health Centre; Department of Epidemiology, Biostatistics and Occupational Health (Dayan, Basso), McGill University, Montréal, Que.; Department of Obstetrics and Gynaecology, and School of Population and Public Health (Joseph), University of British Columbia, Vancouver, BC; Children's Hospital of Eastern Ontario Research Institute (Fell); School of Epidemiology and Public Health (Fell), University of Ottawa, Ottawa, Ont.; Department of Medicine and Obstetrics and Gynecology (Laskin), University of Toronto; TRIO Fertility (Laskin); ICES (Park, Luo, Guan, Ray, Fell); Department of Medicine (Ray), St. Michael's Hospital, Toronto, Ont
| | - Jun Guan
- Department of Medicine and Research Institute (Dayan), Department of Obstetrics and Gynecology (Basso), McGill University Health Centre; Department of Epidemiology, Biostatistics and Occupational Health (Dayan, Basso), McGill University, Montréal, Que.; Department of Obstetrics and Gynaecology, and School of Population and Public Health (Joseph), University of British Columbia, Vancouver, BC; Children's Hospital of Eastern Ontario Research Institute (Fell); School of Epidemiology and Public Health (Fell), University of Ottawa, Ottawa, Ont.; Department of Medicine and Obstetrics and Gynecology (Laskin), University of Toronto; TRIO Fertility (Laskin); ICES (Park, Luo, Guan, Ray, Fell); Department of Medicine (Ray), St. Michael's Hospital, Toronto, Ont
| | - Joel G Ray
- Department of Medicine and Research Institute (Dayan), Department of Obstetrics and Gynecology (Basso), McGill University Health Centre; Department of Epidemiology, Biostatistics and Occupational Health (Dayan, Basso), McGill University, Montréal, Que.; Department of Obstetrics and Gynaecology, and School of Population and Public Health (Joseph), University of British Columbia, Vancouver, BC; Children's Hospital of Eastern Ontario Research Institute (Fell); School of Epidemiology and Public Health (Fell), University of Ottawa, Ottawa, Ont.; Department of Medicine and Obstetrics and Gynecology (Laskin), University of Toronto; TRIO Fertility (Laskin); ICES (Park, Luo, Guan, Ray, Fell); Department of Medicine (Ray), St. Michael's Hospital, Toronto, Ont
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Basso O, Weinberg CR, D'Aloisio AA, Sandler DP. Maternal age at birth and daughters' subsequent childlessness. Hum Reprod 2019; 33:311-319. [PMID: 29211842 DOI: 10.1093/humrep/dex350] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2017] [Accepted: 11/03/2017] [Indexed: 12/29/2022] Open
Abstract
STUDY QUESTION Does maternal age at a daughter's birth predict her subsequent probability of lifelong childlessness? SUMMARY ANSWER In this study population, women born to older mothers were more likely to be childless. WHAT IS KNOWN ALREADY Although maternal age at childbearing is increasing in many countries, there is limited evidence on whether being born to older parents may influence offspring fertility. STUDY DESIGN SIZE AND DURATION This analysis included 43 135 women from the US-based Sister Study, a cohort study of 50 884 sisters of women with breast cancer recruited between 2003 and 2009. PARTICIPANTS/MATERIALS, SETTING, METHODS Participants had no breast cancer at baseline. Women were included in the analytic sample if they were born between 1930 and 1964 and were at least 44 years old at enrolment. Median age when reproductive history was last ascertained was 63.8 years. We estimated relative risks (RR) and 95% CI of lifelong childlessness as a function of maternal age at birth, using multivariable log-binomial models, including total number of siblings, birth order, socioeconomic indicators of the family of origin, race and birth cohort. We examined the association in different subgroups and in a sibling-matched analysis including 802 sister pairs discordant for childlessness. MAIN RESULTS AND ROLE OF CHANCE Compared with women born to 20-24-year-old mothers, those born to mothers aged 25-29, 30-34 and ≥35 years were more likely to be childless [RR (95% CI): 1.21 (1.14-1.29), 1.30 (1.22-1.39) and 1.40 (1.31-1.50), respectively]. The association was consistent in strata defined by birth cohort, number of siblings, birth order, and participant's educational level, as well as within sister pairs. Overall, we found weak evidence for an independent contribution of paternal age at birth to the daughter's probability of childlessness. LIMITATIONS REASONS FOR CAUTION All participants had at least one sister, and all information was self-reported. We had no knowledge of whether childlessness was intentional and found only a modest association between maternal age at birth and self-reported indicators of infertility. Still, the association with childlessness was highly consistent. WIDER IMPLICATIONS OF THE FINDING Given the widespread tendency to delay childbearing, evaluating the influence of maternal age at birth on offspring fertility is a public health priority. STUDY FUNDING/COMPETING INTERESTS This research was supported in part by the Intramural Research Programme of the NIH, National Institute of Environmental Health Sciences (Z01-ES044005). The authors report no conflict of interest.
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Affiliation(s)
- O Basso
- Department of Obstetrics and Gynecology, Royal Victoria Hospital, Research Institute of McGill University Health Centre, Montreal, Canada H4A 3J1.,Department of Epidemiology, Biostatistics, and Occupational Health, McGill University, Montreal, Canada H3A 1A2
| | - C R Weinberg
- Biostatistics and Computational Biology Branch, National Institute of Environmental Health Sciences, Research Triangle Park 27709, USA
| | - A A D'Aloisio
- Social & Scientific Systems Inc., Durham, NC 27703, USA
| | - D P Sandler
- Epidemiology Branch, National Institute of Environmental Health Sciences, Research Triangle Park 27709, USA
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22
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Ahrens KA, Hutcheon JA, Ananth CV, Basso O, Briss PA, Ferré CD, Frederiksen BN, Harper S, Hernández‐Díaz S, Hirai AH, Kirby RS, Klebanoff MA, Lindberg L, Mumford SL, Nelson HD, Platt RW, Rossen LM, Stuebe AM, Thoma ME, Vladutiu CJ, Moskosky S. Report of the Office of Population Affairs' expert work group meeting on short birth spacing and adverse pregnancy outcomes: Methodological quality of existing studies and future directions for research. Paediatr Perinat Epidemiol 2019; 33:O5-O14. [PMID: 30300948 PMCID: PMC6378402 DOI: 10.1111/ppe.12504] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/01/2018] [Revised: 08/09/2018] [Accepted: 08/12/2018] [Indexed: 12/22/2022]
Abstract
BACKGROUND The World Health Organization (WHO) recommends that women wait at least 24 months after a livebirth before attempting a subsequent pregnancy to reduce the risk of adverse maternal, perinatal, and infant health outcomes. However, the applicability of the WHO recommendations for women in the United States is unclear, as breast feeding, nutrition, maternal age at first birth, and total fertility rate differs substantially between the United States and the low- and middle-resource countries upon which most of the evidence is based. METHODS To inform guideline development for birth spacing specific to women in the United States, the Office of Population Affairs (OPA) convened an expert work group meeting in Washington, DC, on 14-15 September 2017 among reproductive, perinatal, paediatric, social, and public health epidemiologists; obstetrician-gynaecologists; biostatisticians; and experts in evidence synthesis related to women's health. RESULTS Presentations and discussion topics included the methodological quality of existing studies, evaluation of the evidence for causal effects of short interpregnancy intervals on adverse perinatal and maternal health outcomes, good practices for future research, and identification of research gaps and priorities for future work. CONCLUSIONS This report provides an overview of the presentations, discussions, and conclusions from the expert work group meeting.
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Affiliation(s)
- Katherine A. Ahrens
- Office of Population AffairsOffice of the Assistant Secretary for HealthRockvilleMaryland
| | - Jennifer A. Hutcheon
- Department of Obstetrics and GynaecologyUniversity of British ColumbiaVancouverBritish ColumbiaCanada
| | - Cande V. Ananth
- Department of Obstetrics and GynecologyVagelos College of Physicians and SurgeonsColumbia UniversityNew YorkNew York,Department of EpidemiologyJoseph L. Mailman School of Public HealthColumbia UniversityNew YorkNew York
| | - Olga Basso
- Department of Obstetrics and GynecologyRoyal Victoria HospitalResearch Institute of McGill University Health CentreMontrealQuebecCanada,Department of Epidemiology, Biostatistics and Occupational HealthMcGill UniversityMontrealQuebecCanada
| | - Peter A. Briss
- National Center for Chronic Disease Prevention and Health Promotion Centers for Disease Control and PreventionAtlantaGeorgia
| | - Cynthia D. Ferré
- Maternal and Infant Health BranchDivision of Reproductive HealthNational Center for Chronic Disease Prevention and Health PromotionCenters for Disease Control and PreventionAtlantaGeorgia
| | - Brittni N. Frederiksen
- Office of Population AffairsOffice of the Assistant Secretary for HealthRockvilleMaryland
| | - Sam Harper
- Department of Epidemiology, Biostatistics and Occupational HealthMcGill UniversityMontrealQuebecCanada
| | - Sonia Hernández‐Díaz
- Department of EpidemiologyHarvard T. H. Chan School of Public HealthBostonMassachusetts
| | - Ashley H. Hirai
- US Department of Health and Human ServicesHealth Resources and Services Administration, Maternal and Child Health BureauOffice of Epidemiology and ResearchRockvilleMaryland
| | - Russell S. Kirby
- Department of Community and Family HealthUniversity of South Florida College of Public HealthTampaFlorida
| | - Mark A. Klebanoff
- Center for Perinatal ResearchDepartments of Pediatrics and Obstetrics and Gynecology and Division of EpidemiologyThe Research Institute at Nationwide Children's HospitalThe Ohio State UniversityColumbusOhio
| | | | - Sunni L. Mumford
- Division of Intramural Population Health Research, Epidemiology BranchNational Institute of Child Health and Human DevelopmentBethesdaMaryland
| | - Heidi D. Nelson
- Department of Medical Informatics and Clinical EpidemiologyOregon Health & Science UniversityPortlandOregon
| | - Robert W. Platt
- Department of Epidemiology, Biostatistics and Occupational HealthMcGill UniversityMontrealQuebecCanada
| | - Lauren M. Rossen
- Reproductive Statistics BranchDivision of Vital StatisticsNational Center for Health StatisticsCenters for Disease Control and PreventionHyattsvilleMaryland
| | - Alison M. Stuebe
- Department of Obstetrics and GynecologyDepartment of Maternal and Child HealthGillings School of Global Public HealthUniversity of North Carolina School of MedicineChapel HillNorth Carolina
| | - Marie E. Thoma
- Department of Family ScienceUniversity of MarylandCollege ParkMaryland
| | - Catherine J. Vladutiu
- US Department of Health and Human ServicesHealth Resources and Services Administration, Maternal and Child Health BureauOffice of Epidemiology and ResearchRockvilleMaryland
| | - Susan Moskosky
- Office of Population AffairsOffice of the Assistant Secretary for HealthRockvilleMaryland
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Hutcheon JA, Moskosky S, Ananth CV, Basso O, Briss PA, Ferré CD, Frederiksen BN, Harper S, Hernández‐Díaz S, Hirai AH, Kirby RS, Klebanoff MA, Lindberg L, Mumford SL, Nelson HD, Platt RW, Rossen LM, Stuebe AM, Thoma ME, Vladutiu CJ, Ahrens KA. Good practices for the design, analysis, and interpretation of observational studies on birth spacing and perinatal health outcomes. Paediatr Perinat Epidemiol 2019; 33:O15-O24. [PMID: 30311958 PMCID: PMC6378590 DOI: 10.1111/ppe.12512] [Citation(s) in RCA: 47] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/01/2018] [Revised: 08/22/2018] [Accepted: 08/25/2018] [Indexed: 12/04/2022]
Abstract
BACKGROUND Meta-analyses of observational studies have shown that women with a shorter interpregnancy interval (the time from delivery to start of a subsequent pregnancy) are more likely to experience adverse pregnancy outcomes, such as preterm delivery or small for gestational age birth, than women who space their births further apart. However, the studies used to inform these estimates have methodological shortcomings. METHODS In this commentary, we summarise the discussions of an expert workgroup describing good practices for the design, analysis, and interpretation of observational studies of interpregnancy interval and adverse perinatal health outcomes. RESULTS We argue that inferences drawn from research in this field will be improved by careful attention to elements such as: (a) refining the research question to clarify whether the goal is to estimate a causal effect vs describe patterns of association; (b) using directed acyclic graphs to represent potential causal networks and guide the analytic plan of studies seeking to estimate causal effects; (c) assessing how miscarriages and pregnancy terminations may have influenced interpregnancy interval classifications; (d) specifying how key factors such as previous pregnancy loss, pregnancy intention, and maternal socio-economic position will be considered; and (e) examining if the association between interpregnancy interval and perinatal outcome differs by factors such as maternal age. CONCLUSION This commentary outlines the discussions of this recent expert workgroup, and describes several suggested principles for study design and analysis that could mitigate many potential sources of bias.
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Affiliation(s)
- Jennifer A. Hutcheon
- Department of Obstetrics and GynaecologyUniversity of British ColumbiaVancouverBritish ColumbiaCanada
| | - Susan Moskosky
- Office of Population AffairsOffice of the Assistant Secretary for HealthRockvilleMaryland
| | - Cande V. Ananth
- Department of Obstetrics and GynecologyIrving College of Physicians and SurgeonsColumbia UniversityNew YorkNew York,Department of EpidemiologyJoseph L. Mailman School of Public HealthColumbia UniversityNew YorkNew York
| | - Olga Basso
- Department of Obstetrics and GynecologyRoyal Victoria HospitalResearch Institute of McGill University Health CentreMontrealQuebecCanada,Department of Epidemiology, Biostatistics, and Occupational HealthMcGill UniversityMontrealQuebecCanada
| | - Peter A. Briss
- National Center for Chronic Disease Prevention and Health PromotionCenters for Disease Control and PreventionAtlantaGeorgia
| | - Cynthia D. Ferré
- Maternal and Infant Health BranchDivision of Reproductive HealthNational Center for Chronic Disease Prevention and Health PromotionCenters for Disease Control and PreventionAtlantaGeorgia
| | - Brittni N. Frederiksen
- Office of Population AffairsOffice of the Assistant Secretary for HealthRockvilleMaryland
| | - Sam Harper
- Department of Epidemiology, Biostatistics, and Occupational HealthMcGill UniversityMontrealQuebecCanada
| | - Sonia Hernández‐Díaz
- Department of EpidemiologyHarvard T. H. Chan School of Public HealthBostonMassachusetts
| | - Ashley H. Hirai
- US Department of Health and Human ServicesHealth Resources and Services AdministrationMaternal and Child Health BureauOffice of Epidemiology and ResearchRockvilleMaryland
| | - Russell S. Kirby
- Department of Community and Family HealthUniversity of South Florida College of Public HealthTampaFlorida
| | - Mark A. Klebanoff
- Division of EpidemiologyDepartments of Pediatrics and Obstetrics and GynecologyCenter for Perinatal ResearchThe Research Institute at Nationwide Children's HospitalThe Ohio State UniversityColumbus Ohio
| | | | - Sunni L. Mumford
- Epidemiology BranchDivision of Intramural Population Health ResearchNational Institute of Child Health and Human DevelopmentBethesdaMaryland
| | - Heidi D. Nelson
- Department of Medical Informatics and Clinical EpidemiologyOregon Health and Science UniversityPortlandOregon
| | - Robert W. Platt
- Department of Epidemiology, Biostatistics, and Occupational HealthMcGill UniversityMontrealQuebecCanada
| | - Lauren M. Rossen
- Reproductive Statistics BranchDivision of Vital StatisticsCenters for Disease Control and PreventionNational Center for Health StatisticsHyattsvilleMaryland
| | - Alison M. Stuebe
- Department of Obstetrics and GynecologyUniversity of North Carolina School of MedicineChapel HillNorth Carolina,Department of Maternal and Child HealthGillings School of Global Public HealthChapel HillNorth Carolina
| | - Marie E. Thoma
- Department of Family ScienceUniversity of MarylandCollege ParkMaryland
| | - Catherine J. Vladutiu
- US Department of Health and Human ServicesHealth Resources and Services AdministrationMaternal and Child Health BureauOffice of Epidemiology and ResearchRockvilleMaryland
| | - Katherine A. Ahrens
- Office of Population AffairsOffice of the Assistant Secretary for HealthRockvilleMaryland
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24
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Dayan N, Joseph K, Fell DB, Laskin CA, Basso O, Park A, Luo J, Guan J, Ray JG. 589: Assisted reproduction and severe maternal morbidity. Am J Obstet Gynecol 2019. [DOI: 10.1016/j.ajog.2018.11.611] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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25
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Grandi SM, Reynier P, Platt RW, Basso O, Filion KB. The timing of onset of hypertensive disorders in pregnancy and the risk of incident hypertension and cardiovascular disease. Int J Cardiol 2018; 270:273-275. [DOI: 10.1016/j.ijcard.2018.06.059] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/07/2018] [Revised: 05/29/2018] [Accepted: 06/13/2018] [Indexed: 11/29/2022]
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26
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Basso O, Lynch C. The society for pediatric and perinatal epidemiologic research: 31st Annual meeting summary. Paediatr Perinat Epidemiol 2018; 32:e1. [PMID: 30211449 DOI: 10.1111/ppe.12502] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/06/2018] [Accepted: 08/09/2018] [Indexed: 11/28/2022]
Affiliation(s)
- Olga Basso
- Department of Obstetrics and Gynaecology, Royal Victoria Hospital, Research Institute of McGill University Health Centre, Montreal, Quebec, Canada.,Department of Epidemiology, Biostatistics, and Occupational Health, McGill University, Montreal, Quebec, Canada
| | - Courtney Lynch
- Department of Obstetrics and Gynaecology, The Ohio State University College of Medicine, Columbus, Ohio.,Division of Epidemiology, The Ohio State University College of Public Health, Columbus, Ohio
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Abstract
Purpose of review Human reproduction is a common process and one that unfolds over a relatively short time, but pregnancy and birth processes are challenging to study. Selection occurs at every step of this process (e.g., infertility, early pregnancy loss, and stillbirth), adding substantial bias to estimated exposure-outcome associations. Here we focus on selection in perinatal epidemiology, specifically, how it affects research question formulation, feasible study designs, and interpretation of results. Recent findings Approaches have recently been proposed to address selection issues in perinatal epidemiology. One such approach is the ongoing pregnancies denominator for gestation-stratified analyses of infant outcomes. Similarly, bias resulting from left truncation has recently been termed "live birth bias," and a proposed solution is to control for common causes of selection variables (e.g., fecundity, fetal loss) and birth outcomes. However, these approaches have theoretical shortcomings, conflicting with the foundational epidemiologic concept of populations at risk for a given outcome. Summary We engage with epidemiologic theory and employ thought experiments to demonstrate the problems of using denominators that include units not "at risk" of the outcome. Fundamental (and commonsense) concerns of outcome definition and analysis (e.g., ensuring that all study participants are at risk for the outcome) should take precedence in formulating questions and analysis approach, as should choosing questions that stakeholders care about. Selection and resulting biases in human reproductive processes complicate estimation of unbiased exposure- outcome associations, but we should not focus solely (or even mostly) on minimizing such biases.
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Affiliation(s)
- Jonathan M Snowden
- School of Public Health, Oregon Health and Science University-Portland State University, 3181 SW Sam Jackson Park Rd, Mail Code: CB-669, Portland, OR 97239-3098, USA
- Department of Obstetrics and Gynecology, Oregon Health and Science University, 3181 SW Sam Jackson Park Rd, Mail Code: L-466, Portland, OR 97239-3098, USA
| | - Marit L Bovbjerg
- College of Public Health and Human Sciences, Oregon State University, Milam Hall 103, Corvallis, OR 97331, USA
| | - Mekhala Dissanayake
- Department of Obstetrics and Gynecology, Oregon Health and Science University, 3181 SW Sam Jackson Park Rd, Mail Code: L-466, Portland, OR 97239-3098, USA
| | - Olga Basso
- Department of Obstetrics & Gynecology; Research Institute of the McGill University Health Centre
- Department of Epidemiology, Biostatistics, and Occupational Health McGill University, Purvis Hall, 1020 Pine Avenue West, Montreal QC H3A 1A2, Canada
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28
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Affiliation(s)
- Gabriel Altit
- Neonatology, Montreal Children's Hospital, McGill University, Montreal, Canada. .,Department of Epidemiology, Biostatistics and Occupational Health, McGill University, Montreal, Canada.
| | - Olga Basso
- Department of Epidemiology, Biostatistics and Occupational Health, McGill University, Montreal, Canada.,Obstetrics & Gynecology, Royal Victoria Hospital, McGill University, Montreal, Canada
| | - Sonia M Grandi
- Department of Epidemiology, Biostatistics and Occupational Health, McGill University, Montreal, Canada
| | - Seungmi Yang
- Department of Epidemiology, Biostatistics and Occupational Health, McGill University, Montreal, Canada
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29
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Leung SOA, Basso O, Mitric C, Zeng X, Jardon K, Souhami L, Alfieri J, Arseneau J, Fu L, Artho G, Reinhold C, Gilbert L. Choosing Wisely in Low Grade, Low Risk Endometrial Cancer Patients: the Value of Pre-Operative MRI, Lymph Node Dissection, and Postoperative Detailed Pathology. Journal of Obstetrics and Gynaecology Canada 2018. [DOI: 10.1016/j.jogc.2018.03.074] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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Abstract
OBJECTIVE Using a simple simulation, we illustrate why associations estimated from studies restricted to preterm births cannot be interpreted causally. DESIGN, SETTING AND POPULATION Data simulation involving a hypothetical cohort of fetuses who may be healthy or have one or more of four pathological factors (termed A through D, increasing in severity) with known effects on gestational length and risk of mortality. We focus on babies born at ≤32 weeks of gestation. METHODS We visually represent the simulated population and compare the association between A (which may represent pre-eclampsia) and neonatal death. We then repeat the exercise with D (standing in for chorioamnionitis) as the exposure of interest. MAIN OUTCOME MEASURES Odds ratios of neonatal death in the simulated data. RESULTS In most weeks, and for both A and D, the calculated odds ratios are substantially biased and underestimate the true risk of neonatal death associated with each pathology. For example, factor A has a true causal odds ratio of 1.50, yet it appears protective among births ≤32 weeks (estimated crude odds ratio 0.39; gestational age-adjusted odds ratio 0.71). CONCLUSIONS Among very preterm births, virtually all babies are born with pathologies that increase the risk of adverse outcomes. Hence, babies exposed to one factor (e.g. pre-eclampsia) are compared with babies who have a mix of other pathologies. Such selection bias affects studies carried out among very preterm births (e.g. where pre-eclampsia appears to reduce risk of adverse neonatal outcomes). TWEETABLE ABSTRACT Selection bias affects studies of preterm births, complicating interpretation.
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Affiliation(s)
- J M Snowden
- School of Public Health, Oregon Health and Science University/Portland State University, Portland, OR, USA
- Department of Obstetrics & Gynecology, Oregon Health and Science University, Portland, OR, USA
| | - O Basso
- Department of Obstetrics & Gynecology, Research Institute of the McGill University Health Centre, Montreal, QC, Canada
- Department of Epidemiology, Biostatistics & Occupational Health, McGill University, Montreal, QC, Canada
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31
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Abstract
Preterm delivery is one of the strongest predictors of neonatal mortality. A given exposure may increase neonatal mortality directly, or indirectly by increasing the risk of preterm birth. Efforts to assess these direct and indirect effects are complicated by the fact that neonatal mortality arises from two distinct denominators (i.e. two risk sets). One risk set comprises fetuses, susceptible to intrauterine pathologies (such as malformations or infection), which can result in neonatal death. The other risk set comprises live births, who (unlike fetuses) are susceptible to problems of immaturity and complications of delivery. In practice, fetal and neonatal sources of neonatal mortality cannot be separated-not only because of incomplete information, but because risks from both sources can act on the same newborn. We use simulations to assess the repercussions of this structural problem. We first construct a scenario in which fetal and neonatal factors contribute separately to neonatal mortality. We introduce an exposure that increases risk of preterm birth (and thus neonatal mortality) without affecting the two baseline sets of neonatal mortality risk. We then calculate the apparent gestational-age-specific mortality for exposed and unexposed newborns, using as the denominator either fetuses or live births at a given gestational age. If conditioning on gestational age successfully blocked the mediating effect of preterm delivery, then exposure would have no effect on gestational-age-specific risk. Instead, we find apparent exposure effects with either denominator. Except for prediction, neither denominator provides a meaningful way to define gestational-age-specific neonatal mortality.
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Affiliation(s)
- Quaker E Harmon
- National Institute of Environmental Health Sciences, P.O. Box 12233, Durham, NC, 27709, USA.
| | - Olga Basso
- Department of Obstetrics and Gynecology, McGill University, Montreal, QC, Canada.,Department of Epidemiology, Biostatistics and Occupational Health, McGill University, Montreal, QC, Canada
| | - Clarice R Weinberg
- Biostatistics and Computational Biology Branch, National Institute of Environmental Health Sciences, Durham, NC, USA
| | - Allen J Wilcox
- National Institute of Environmental Health Sciences, P.O. Box 12233, Durham, NC, 27709, USA
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32
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Drews-Botsch C, Basso O. Society for Paediatric and Perinatal Epidemiology 30th Annual Meeting: Present and Future. Paediatr Perinat Epidemiol 2018; 32:e1-e3. [PMID: 28841749 PMCID: PMC6561473 DOI: 10.1111/ppe.12397] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Carolyn Drews-Botsch
- Department of Epidemiology, Rollins School of Public Health, Emory University, Atlanta, GA
| | - Olga Basso
- Department of Obstetrics and Gynecology, McGill University Health Centre, Montreal, QC, Canada,Department of Epidemiology, Biostatistics, and Occupational Heath, McGill University Health Centre, Montreal, QC, Canada
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33
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Messerlian C, Basso O. Cohort studies in the context of obstetric and gynecologic research: a methodologic overview. Acta Obstet Gynecol Scand 2017; 97:371-379. [DOI: 10.1111/aogs.13272] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2017] [Accepted: 11/22/2017] [Indexed: 11/28/2022]
Affiliation(s)
- Carmen Messerlian
- Department of Environmental Health; Harvard T.H. Chan School of Public Health; Boston MA USA
| | - Olga Basso
- Department of Obstetrics & Gynecology; Royal Victoria Hospital; Research Institute of McGill University Health Center; Canada
- Department of Epidemiology, Biostatistics, and Occupational Health; McGill University; Montreal Canada
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34
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Dayan N, Filion KB, Okano M, Kilmartin C, Reinblatt S, Landry T, Basso O, Udell JA. Cardiovascular Risk Following Fertility Therapy. J Am Coll Cardiol 2017; 70:1203-1213. [DOI: 10.1016/j.jacc.2017.07.753] [Citation(s) in RCA: 45] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/09/2017] [Revised: 07/06/2017] [Accepted: 07/10/2017] [Indexed: 11/30/2022]
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35
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Grandi SM, Vallée-Pouliot K, Reynier P, Eberg M, Platt RW, Arel R, Basso O, Filion KB. Hypertensive Disorders in Pregnancy and the Risk of Subsequent Cardiovascular Disease. Paediatr Perinat Epidemiol 2017; 31:412-421. [PMID: 28816365 DOI: 10.1111/ppe.12388] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
BACKGROUND Hypertensive disorders in pregnancy (HDP) have been shown to predict later risk of cardiovascular disease (CVD). However, previous studies have not accounted for subsequent pregnancies and their complications, which are potential confounders and intermediates of this association. METHODS A cohort of 146 748 women with a first pregnancy was constructed using the Clinical Practice Research Datalink. HDP was defined using diagnostic codes, elevated blood pressure readings, or new use of an anti-hypertensive drug between 18 weeks' gestation and 6 weeks post-partum. The study outcomes were incident CVD and hypertension. Marginal structural Cox models (MSM) were used to account for time-varying confounders and intermediates. Time-fixed exposure defined at the first pregnancy was used in secondary analyses. RESULTS A total of 997 women were diagnosed with incident CVD, and 6812 women were diagnosed with hypertension or received a new anti-hypertensive medication during the follow-up period. Compared with women without HDP, those with HDP had a substantially higher rate of CVD (hazard ratio (HR) 2.2, 95% confidence interval (CI) 1.7, 2.7). In women with HDP, the rate of hypertension was five times that of women without a HDP (HR 5.6, 95% CI 5.1, 6.3). With overlapping 95% CIs, the time-fixed analysis and the MSM produced consistent results for both outcomes. CONCLUSIONS Women with HDP are at increased risk of developing subsequent CVD and hypertension. Similar estimates obtained with the MSM and the time-fixed analysis suggests that subsequent pregnancies do not confound a first episode of HDP and later CVD.
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Affiliation(s)
- Sonia M Grandi
- Department of Epidemiology, Biostatistics and Occupational Health, McGill University, Montreal, QC, Canada
| | - Karine Vallée-Pouliot
- Department of Epidemiology, Biostatistics and Occupational Health, McGill University, Montreal, QC, Canada
| | - Pauline Reynier
- Centre for Clinical Epidemiology, Lady Davis Institute, Jewish General Hospital, Montreal, QC, Canada
| | - Maria Eberg
- Centre for Clinical Epidemiology, Lady Davis Institute, Jewish General Hospital, Montreal, QC, Canada
| | - Robert W Platt
- Department of Epidemiology, Biostatistics and Occupational Health, McGill University, Montreal, QC, Canada.,McGill University Health Center Research Institute, Montreal, QC, Canada.,Department of Pediatrics, McGill University, Montreal, QC, Canada
| | - Roxane Arel
- Department of Family Medicine, St. Mary's Hospital Centre, McGill University, Montreal, QC, Canada
| | - Olga Basso
- Department of Epidemiology, Biostatistics and Occupational Health, McGill University, Montreal, QC, Canada.,McGill University Health Center Research Institute, Montreal, QC, Canada.,Department of Obstetrics and Gynecology, McGill University, Montreal, QC, Canada
| | - Kristian B Filion
- Department of Epidemiology, Biostatistics and Occupational Health, McGill University, Montreal, QC, Canada.,Centre for Clinical Epidemiology, Lady Davis Institute, Jewish General Hospital, Montreal, QC, Canada.,Department of Medicine, McGill University, Montreal, QC, Canada
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36
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Weinberg CR, Shi M, Basso O, DeRoo LA, Harmon Q, Wilcox AJ, Skjærven R. Season of Conception, Smoking, and Preeclampsia in Norway. Environ Health Perspect 2017; 125:067022. [PMID: 28669933 PMCID: PMC5743488 DOI: 10.1289/ehp963] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/14/2016] [Revised: 01/24/2017] [Accepted: 01/25/2017] [Indexed: 05/17/2023]
Abstract
BACKGROUND Preeclampsia (PE) is a dangerous and unpredictable pregnancy complication. A seasonal pattern of risk would suggest that there are potentially preventable environmental contributors, but prior analyses have not adjusted for confounding by PE risk factors that are associated with season of conception. METHODS Seasonal effects were modeled and tested by representing each day of the year as an angle on a unit circle and using trigonometric functions of those angles in predictive models, using "harmonic analysis." We applied harmonic Cox regression to model confounder-adjusted effects of the estimated day of the year of conception on risk of PE for births from the Medical Birth Registry of Norway for deliveries between 1999 and 2009. We also examined effect measure modification by parity, latitude (region), fetal sex, and smoking. RESULTS In adjusted models, PE risk was related to season, with higher risk in spring conceptions and lower risk in autumn conceptions, with a risk amplitude (maximum compared with minimum) of about 20%. The pattern replicated across subpopulations defined by parity, latitude (region), fetal sex, and smoking. CONCLUSIONS These results suggest that there is a seasonal driver for PE, with effects that are not modified by parity, latitude, fetal sex, or smoking. https://doi.org/10.1289/EHP963.
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Affiliation(s)
- Clarice R Weinberg
- Biostatistics and Computational Biology Branch, National Institute of Environmental Health Sciences , Research Triangle Park, North Carolina, USA
| | - Min Shi
- Biostatistics and Computational Biology Branch, National Institute of Environmental Health Sciences , Research Triangle Park, North Carolina, USA
| | - Olga Basso
- Department of Obstetrics and Gynecology, McGill University, Montreal, Quebec, Canada
- Department of Epidemiology, Biostatistics and Occupational Health, McGill University, Montreal, Quebec, Canada
| | - Lisa A DeRoo
- Department of Global Public Health and Primary Care, University of Bergen, Bergen, Norway
| | - Quaker Harmon
- Epidemiology Branch, National Institute of Environmental Health Sciences, Research Triangle Park, North Carolina, USA
| | - Allen J Wilcox
- Epidemiology Branch, National Institute of Environmental Health Sciences, Research Triangle Park, North Carolina, USA
| | - Rolv Skjærven
- Department of Global Public Health and Primary Care, University of Bergen, Bergen, Norway
- Norwegian Institute of Public Health, Medical Birth Registry of Norway, Bergen, Norway
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37
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Sun Z, Gilbert L, Ciampi A, Kaufman JS, Basso O. Estimating the Prevalence of Ovarian Cancer Symptoms in Women Aged 50 Years or Older: Problems and Possibilities. Am J Epidemiol 2016; 184:670-680. [PMID: 27737840 DOI: 10.1093/aje/kww086] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2015] [Accepted: 02/02/2016] [Indexed: 02/05/2023] Open
Abstract
Diagnostic testing is recommended in women with "ovarian cancer symptoms." However, these symptoms are nonspecific. The ongoing Diagnosing Ovarian Cancer Early (DOVE) Study in Montreal, Quebec, Canada, provides diagnostic testing to women aged 50 years or older with symptoms lasting for more than 2 weeks and less than 1 year. The prevalence of ovarian cancer in DOVE is 10 times that of large screening trials, prompting us to estimate the prevalence of these symptoms in this population. We sent a questionnaire to 3,000 randomly sampled women in 2014-2015. Overall, 833 women responded; 81.5% reported at least 1 symptom, and 59.7% reported at least 1 symptom within the duration window specified in DOVE. We explored whether such high prevalence resulted from low survey response by applying inverse probability weighting to correct the estimates. Older women and those from deprived areas were less likely to respond, but only age was associated with symptom reporting. Prevalence was similar in early and late responders. Inverse probability weighting had a minimal impact on estimates, suggesting little evidence of nonresponse bias. This is the first study investigating symptoms that have proven to identify a subset of women with a high prevalence of ovarian cancer. However, the high frequency of symptoms warrants further refinements before symptom-triggered diagnostic testing can be implemented.
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Affiliation(s)
- Jørn Olsen
- The Danish Epidemiology Science Centre, Copenhagen-Aarhus, Denmark,
| | - Olga Basso
- The Danish Epidemiology Science Centre, Copenhagen-Aarhus, Denmark
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39
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Fell DB, Buckeridge DL, Platt RW, Kaufman JS, Basso O, Wilson K. Circulating Influenza Virus and Adverse Pregnancy Outcomes: A Time-Series Study. Am J Epidemiol 2016; 184:163-75. [PMID: 27449415 DOI: 10.1093/aje/kww044] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2015] [Accepted: 02/19/2016] [Indexed: 11/14/2022] Open
Abstract
Individual-level epidemiologic studies of pregnancy outcomes after maternal influenza are limited in number and quality and have produced inconsistent results. We used a time-series design to investigate whether fluctuation in influenza virus circulation was associated with short-term variation in population-level rates of preterm birth, stillbirth, and perinatal death in Ontario between 2003 and 2012. Using Poisson regression, we assessed the association between weekly levels of circulating influenza virus and counts of outcomes offset by the number of at-risk gestations during 3 gestational exposure windows. The rate of preterm birth was not associated with circulating influenza level in the week preceding birth (adjusted rate ratio = 1.01, 95% confidence interval: 1.00, 1.02) or in any other exposure window. These findings were robust to alternate specifications of the model and adjustment for potential confounding. Stillbirth and perinatal death rates were similarly not associated with gestational exposure to influenza circulation during late pregnancy. We could not assess mortality outcomes relative to early gestational exposure because of missing dates of conception for many stillbirths. In this time-series study, population-level influenza circulation was not associated with short-term variation in rates of preterm birth, stillbirth, or perinatal death.
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40
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Basso O, Campi R, Frydenberg M, Koch-Henriksen N, Brønnum-Hansen H, Olsen J. Multiple sclerosis in women having children by multiple partners. A population-based study in Denmark. Mult Scler 2016; 10:621-5. [PMID: 15584485 DOI: 10.1191/1352458504ms1099oa] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
We investigated whether having children with multiple men is a risk factor for being diagnosed with multiple sclerosis (MS). We studied a cohort of 151 328 women, of whom 64 704 had different men fathering their children and 86 624 the same partner for all births. Women were included if they had a second or higher parity child between 1973 and 1996. The follow-up for MS ended in 1997. There were a total of 213 cases of MS diagnosed during the study period. We analysed data through Poisson regression models. Women having children with different men were not at higher risk of being diagnosed with MS, with the possible exception of a short period after having a baby with a new partner. Women having children with more than one man may have a higher risk of a pregnancy accelerating the diagnosis of MS but are probably not at an overall higher risk of MS.
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Affiliation(s)
- Olga Basso
- Danish Epidemiology Science Centre, Department of Epidemiology and Social Medicine, University of Aarhus, Aarhus, Denmark.
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41
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Affiliation(s)
- Olga Basso
- Department of Obstetrics and Gynecology, Department of Epidemiology, Biostatistics, and Occupational Health, McGill University, Montreal, QC, Canada
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Abstract
BACKGROUND Gestational-age-specific rates of postnatal endpoints are sometimes estimated with denominators based on fetuses-at-risk (FAR), rather than live births. However, as infants can only be included in the numerator after they are born alive, interpretation of such rates is problematic. METHODS Using simple algebra it can be shown that, at each gestational week, FAR rates of postnatal endpoints are the product of the conventional risk of outcome among live births and the probability of live birth, which increases from near zero early in gestation to close to one in the final weeks. The consequences of such a pattern of live birth on FAR rates are further illustrated in hypothetical scenarios with known conditions. RESULTS FAR rates of postnatal endpoints will generally increase towards the end of pregnancy due to the rising probability of live birth, regardless of the 'true' effect of immaturity on risk. In the presence of an exposure that increases the probability of early birth, the same mechanism will cause FAR rates to be higher in the exposed group, even if the exposure has no effect. CONCLUSIONS Gestational-age-specific FAR rates of postnatal outcomes strongly depend on the probability of live birth. Thus, they reflect neither the causal effect of gestational length, nor that of a given exposure. Indeed, if an exposure shortens gestation, FAR rates will be higher in exposed infants even when the exposure has no impact on the outcome under study. These intrinsic limitations should be taken into account when applying FAR analyses to postnatal endpoints.
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Affiliation(s)
- Olga Basso
- Department of Obstetrics and Gynecology, McGill University, Montreal, QC, Canada.,Department of Epidemiology, Biostatistics, and Occupational Health, McGill University, Montreal, QC, Canada
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Plana-Ripoll O, Li J, Kesmodel US, Olsen J, Parner E, Basso O. Maternal stress before and during pregnancy and subsequent infertility in daughters: a nationwide population-based cohort study. Hum Reprod 2015; 31:454-62. [PMID: 26677955 DOI: 10.1093/humrep/dev309] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2015] [Accepted: 11/20/2015] [Indexed: 01/24/2023] Open
Abstract
STUDY QUESTION Is maternal stress following the death of a close relative before or during pregnancy associated with the risk of infertility in daughters? SUMMARY ANSWER Compared with unexposed women, women whose mothers had experienced bereavement stress during, or in the year before, pregnancy had a similar risk of infertility overall, but those exposed to maternal bereavement during the first trimester had a higher risk of infertility. WHAT IS KNOWN ALREADY Animal studies have shown that prenatal maternal stress results in reduced offspring fertility. In humans, there is evidence that girls who have been prenatally exposed to stress have a more masculine behaviour and a slight delay in having their first child. STUDY DESIGN, SIZE AND DURATION This population-based cohort study, included 660 099 females born in Denmark between 1 January 1973 and 31 December 1993 to mothers of Danish origin and with at least one living relative in the exposure window, and followed the women through 31 December 2011. PARTICIPANTS/MATERIALS, SETTING, METHODS Overall, 13 334 women (2.0%) were considered prenatally exposed to stress because their mother had lost a spouse/partner, a child, a parent, or a sibling during pregnancy or in the year before conception. Infertility was defined as any record of infertility treatment or diagnosis of female infertility. We considered the date of onset as the date of the first appearance of any such record. The association between exposure and outcome was examined using hazard ratios (HR) with 95% confidence intervals (CI). MAIN RESULTS AND THE ROLE OF CHANCE Based on our definition, 40 052 (6.5%) women were infertile in the follow-up period (median age at the end of follow-up: 26.7 years, maximum age: 39 years). Overall, prenatal exposure to maternal stress was not associated with risk of infertility (adjusted HR = 1.04 [CI: 0.95-1.14]). However, women prenatally exposed during the first trimester had a higher estimated risk (adjusted HR = 1.40 [CI: 1.05-1.86]). These findings were consistent in subgroups defined by the relationship of the mother to the deceased and in several sensitivity analyses, including a sibling-matched analysis, and in analyses restricted to women who were married or cohabitating with a man, or to women born at term. LIMITATIONS, REASONS FOR CAUTION We did not have a direct measure of stress, but bereavement due to death of a close relative is likely to be very stressful. We based the timing of exposure on the date of the death of the family member, although the stress may well have started earlier. Infertility was also defined indirectly, and many women in the cohort were too young at the end of the follow-up to have been diagnosed. However, misclassification of the outcome was most likely non-differential, and the similar results from all sensitivity analyses suggest that it is unlikely that the effect observed in first trimester exposure would be due to chance. WIDER IMPLICATIONS OF THE FINDINGS Prenatal exposure to maternal stress in the first trimester may affect the later fecundity of daughters. STUDY FUNDING/COMPETING INTERESTS This study was supported by a grant from the European Research Council (ERC-2010-StG-260242-PROGEURO) to the ProgEuro project (http://progeuro.au.dk). O.P.-R. is partly supported by a fellowship from Aarhus University and a travel grant from Oticon Fonden. The authors report no conflict of interests.
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Affiliation(s)
- O Plana-Ripoll
- Section of Epidemiology, Department of Public Health, Aarhus University, Aarhus, Denmark Department of Epidemiology, Biostatistics and Occupational Health, McGill University, Montreal, Canada
| | - J Li
- Section of Epidemiology, Department of Public Health, Aarhus University, Aarhus, Denmark
| | - U S Kesmodel
- The Fertility Clinic, Department of Obstetrics and Gynecology, Herlev University Hospital, University of Copenhagen, Copenhagen, Denmark
| | - J Olsen
- Section of Epidemiology, Department of Public Health, Aarhus University, Aarhus, Denmark Department of Epidemiology, Fielding School of Public Health, University of California, Los Angeles, CA, USA
| | - E Parner
- Section of Biostatistics, Department of Public Health, Aarhus University, Aarhus, Denmark
| | - O Basso
- Department of Epidemiology, Biostatistics and Occupational Health, McGill University, Montreal, Canada Department of Obstetrics and Gynecology, McGill University, Montreal, Canada
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Dionne MD, Deneux-Tharaux C, Dupont C, Basso O, Rudigoz RC, Bouvier-Colle MH, Le Ray C. Duration of Expulsive Efforts and Risk of Postpartum Hemorrhage in Nulliparous Women: A Population-Based Study. PLoS One 2015; 10:e0142171. [PMID: 26555447 PMCID: PMC4640501 DOI: 10.1371/journal.pone.0142171] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2015] [Accepted: 10/07/2015] [Indexed: 11/19/2022] Open
Abstract
Objective To assess the specific association between the duration of expulsive efforts and the risk of postpartum hemorrhage. Methods Population-based cohort-nested case-control study of nulliparous women delivering vaginally in 106 French maternity units between December 2004 and November 2006, including 3,852 women with PPH (blood loss ≥ 500 mL and/or peripartum Hb decrease ≥ 2 g/dL), 1,048 of them severe (peripartum Hb decrease ≥ 4 g/dL or transfusion of ≥ 2 units of red blood cells), and 762 controls from a representative sample of deliveries without hemorrhage in the same population. The association between duration of expulsive efforts and postpartum hemorrhage was estimated by multilevel logistic regression models adjusted for individual and hospital characteristics. Results Median duration of expulsive efforts was 18 minutes among controls, 20 minutes among postpartum hemorrhage and 23 minutes among severe postpartum hemorrhage (p<0.01). Duration of expulsive efforts was significantly, positively, and linearly associated with both postpartum hemorrhage and severe postpartum hemorrhage. After adjustment for other risk factors, every additional 10 minutes of expulsive efforts was associated with about a 10% increase in the risk of postpartum hemorrhage (aOR = 1.11 [1.02–1.21]) and severe postpartum hemorrhage (aOR = 1.14 [1.03–1.27]). Oxytocin during labor, duration of active phase of labor, forceps use, episiotomy, perineal tears, and birth weight were also independently associated with both risks. Conclusion Duration of expulsive efforts was independently associated with postpartum hemorrhage and severe postpartum hemorrhage. Interventions to shorten the duration of this stage, such as oxytocin, forceps, and episiotomy, are also associated with higher risks of postpartum hemorrhage. Beyond duration, other aspects of the management of active second stage should be evaluated as some might allow it to last longer with a minimal increase in postpartum hemorrhage risk.
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Affiliation(s)
- Marie-Danielle Dionne
- Inserm UMR 1153, Obstetrical, Perinatal and Pediatric Epidemiology Research Team (Epopé), Center for Epidemiology and Statistics Sorbonne Paris Cité, DHU Risks in pregnancy, Paris Descartes University, Paris, France
- Department of Obstetrics and Gynecology, McGill University, Montreal, Canada
- Montreal University Health Center, Montreal, Canada
| | - Catherine Deneux-Tharaux
- Inserm UMR 1153, Obstetrical, Perinatal and Pediatric Epidemiology Research Team (Epopé), Center for Epidemiology and Statistics Sorbonne Paris Cité, DHU Risks in pregnancy, Paris Descartes University, Paris, France
| | - Corinne Dupont
- Aurore perinatal network, Hôpital de la Croix Rousse, Hospices Civils de Lyon, EA 4129 Université Lyon1, Lyon, France
| | - Olga Basso
- Department of Obstetrics and Gynecology, McGill University, Montreal, Canada
- Department of Epidemiology, Biostatistics and Occupational Health, McGill University, Montreal, Canada
| | - René-Charles Rudigoz
- Aurore perinatal network, Hôpital de la Croix Rousse, Hospices Civils de Lyon, EA 4129 Université Lyon1, Lyon, France
| | - Marie-Hélène Bouvier-Colle
- Inserm UMR 1153, Obstetrical, Perinatal and Pediatric Epidemiology Research Team (Epopé), Center for Epidemiology and Statistics Sorbonne Paris Cité, DHU Risks in pregnancy, Paris Descartes University, Paris, France
| | - Camille Le Ray
- Inserm UMR 1153, Obstetrical, Perinatal and Pediatric Epidemiology Research Team (Epopé), Center for Epidemiology and Statistics Sorbonne Paris Cité, DHU Risks in pregnancy, Paris Descartes University, Paris, France
- Port Royal Maternity, Cochin-Broca-Hôtel Dieu Hospital, Assistance Publique Hôpitaux de Paris, Paris Descartes University, Paris, France
- * E-mail:
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Abstract
OBJECTIVE We sought to determine whether midpregnancy antioxidant levels are associated with preeclampsia, overall and by timing of onset. STUDY DESIGN We carried out a case-control study, nested within a cohort of 5337 pregnant women in Montreal, Quebec, Canada. Blood samples obtained at 24-26 weeks were assayed for nonenzymatic antioxidant levels among cases of preeclampsia (n = 111) and unaffected controls (n = 441). We excluded women diagnosed with gestational hypertension only. We used logistic regression with the z-score of each antioxidant level as the main predictor variable for preeclampsia risk. We further stratified early-onset (<34 weeks) and late-onset preeclampsia and carried out multinomial logistic regression. Finally, we assessed associations between antioxidant biomarkers and timing of onset (in weeks) by Cox regression, with appropriate selection weights. We summed levels of correlated biomarkers (r(2) > 0.3) and log-transformed positively skewed distributions. We adjusted for body mass index, nulliparity, preexisting diabetes, hypertension, smoking, and proxies for ethnicity and socioeconomic status. RESULTS The odds ratios for α-tocopherol, α-tocopherol:cholesterol, lycopene, lutein, and carotenoids (sum of α-carotene, β-carotene, anhydrolutein, α-cryptoxanthin, and β-cryptoxanthin) suggested an inverse association between antioxidant levels and overall preeclampsia risk; however, only lutein was significantly associated with overall preeclampsia in adjusted models (odds ratio, 0.60; 95% confidence interval, 0.46-0.77) per SD. In multinomial logistic models, the relative risk ratio (RRR) estimates for the early-onset subgroup were farther from the null than those for the late-onset subgroup. The ratio of α-tocopherol to cholesterol and retinol were significantly associated with early- but not late-onset preeclampsia: RRRs (95% confidence intervals) for early-onset preeclampsia 0.67 (0.46-0.99) and 1.61 (1.12-2.33), respectively. Lutein was significantly associated with both early- and late-onset subtypes in adjusted models; RRRs 0.53 (0.35-0.80) and 0.62 (0.47-0.82), respectively. Survival analyses confirmed these trends. CONCLUSION Most antioxidants were more strongly associated with early-onset preeclampsia, suggesting that oxidative stress may play a greater role in the pathophysiology of early-onset preeclampsia. Alternatively, reverse causality may explain this pattern. Lutein was associated with both early- and late-onset preeclampsia and may be a promising nutrient to consider in preeclampsia prevention trials, if this finding is corroborated.
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Affiliation(s)
- Jacqueline M Cohen
- Department of Epidemiology, Biostatistics, and Occupational Health, Faculty of Medicine, McGill University, Montreal, Quebec, Canada; Center for Clinical Epidemiology, Lady Davis Institute for Medical Research, Jewish General Hospital, Montreal, Quebec, Canada.
| | - Michael S Kramer
- Department of Epidemiology, Biostatistics, and Occupational Health, Faculty of Medicine, McGill University, Montreal, Quebec, Canada; Department of Pediatrics, Faculty of Medicine, McGill University, Montreal, Quebec, Canada
| | - Robert W Platt
- Department of Epidemiology, Biostatistics, and Occupational Health, Faculty of Medicine, McGill University, Montreal, Quebec, Canada; Department of Pediatrics, Faculty of Medicine, McGill University, Montreal, Quebec, Canada
| | - Olga Basso
- Department of Epidemiology, Biostatistics, and Occupational Health, Faculty of Medicine, McGill University, Montreal, Quebec, Canada; Department of Obstetrics and Gynecology, Faculty of Medicine, McGill University, Montreal, Quebec, Canada
| | - Rhobert W Evans
- Department of Epidemiology, University of Pittsburgh School of Medicine, Pittsburgh, PA
| | - Susan R Kahn
- Department of Epidemiology, Biostatistics, and Occupational Health, Faculty of Medicine, McGill University, Montreal, Quebec, Canada; Department of Medicine, Faculty of Medicine, McGill University, Montreal, Quebec, Canada; Center for Clinical Epidemiology, Lady Davis Institute for Medical Research, Jewish General Hospital, Montreal, Quebec, Canada
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Liu S, Basso O, Kramer MS. Liu et al. respond to "isolating preterm birth to assess its impact". Am J Epidemiol 2015; 182:762. [PMID: 26409237 DOI: 10.1093/aje/kwv167] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2015] [Accepted: 06/17/2015] [Indexed: 11/14/2022] Open
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Liu S, Basso O, Kramer MS. Association between unintentional injury during pregnancy and excess risk of preterm birth and its neonatal sequelae. Am J Epidemiol 2015; 182:750-8. [PMID: 26409238 DOI: 10.1093/aje/kwv165] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2015] [Accepted: 04/24/2015] [Indexed: 11/13/2022] Open
Abstract
The sequelae of preterm births may differ, depending on whether birth follows an acute event or a chronic condition. In a population-based cohort study of 2,711,645 Canadian hospital deliveries from 2003 to 2012, 3,059 women experienced unintentional injury during pregnancy. We assessed the impact of the acute event on pregnancy outcome and on neonatal complications, such as nontraumatic intracranial hemorrhage, respiratory distress syndrome, intubation, and death. We adjusted for maternal age, parity, pregnancy conditions, and (for neonates) gestational age in logistic regression analyses. Injury was significantly associated with fetal mortality and early preterm delivery. For preterm infants born to injured women during the hospitalization for injury versus those born to noninjured women, the adjusted odds ratios were 2.25 (95% confidence interval (CI): 1.23, 4.17) for neonatal death, 2.44 (95% CI: 1.76, 3.37) for respiratory distress, 2.20 (95% CI: 1.26, 3.84) for nontraumatic intracranial hemorrhage, and 2.17 (95% CI: 1.60, 2.96) for intubation, despite more favorable fetal growth in those born to noninjured women (adjusted birth-weight-for-gestational-age z score: 0.154 vs. 0.024, P = 0.041; small-for-gestational-age rate: 4.5% vs. 9.5%, P = 0.001). Our findings suggest that adaptation to the suboptimal intrauterine environment underlying chronic causes of preterm birth may protect preterm infants from adverse sequelae.
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Basso O. Invited Commentary: Induced Abortion and the Risk of Preeclampsia in a Subsequent Pregnancy. Am J Epidemiol 2015; 182:670-2. [PMID: 26377956 DOI: 10.1093/aje/kwv182] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2015] [Accepted: 06/02/2015] [Indexed: 11/12/2022] Open
Abstract
Although it is well established that a having a pregnancy that ends in a birth protects against subsequent preeclampsia, it is unclear whether a pregnancy ending in miscarriage or induced abortion confers any protection. In this issue of the Journal, Parker et al. (Am J Epidemiol. 2015;182(8):663-669) examine whether, in nulliparous women, a history of induced abortion is associated with a lower risk of preeclampsia in a later pregnancy, focusing on the hypothesis that endometrial injury facilitates later implantation. The authors take advantage of data obtained by linking several Finnish population-based registries that include detailed data on induced abortions, although information on miscarriages was of lower quality. Parker et al. found a modest reduction in risk among women with a history of induced abortion. However, there was little evidence that risk differed between women who had medical abortions and those who had surgical abortions (the latter of which is presumably associated with a higher degree of injury). History of miscarriage was not associated with preeclampsia risk. Although the study by Parker et al. adds to the evidence that suggests that women with a history of induced abortion have a lower risk of preeclampsia, it is difficult to evaluate whether the observed association is due to having had a previous pregnancy (however short) versus none, to confounding, or to an actual effect of induced abortion.
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Cohen JM, Beddaoui M, Kramer MS, Platt RW, Basso O, Kahn SR. Maternal Antioxidant Levels in Pregnancy and Risk of Preeclampsia and Small for Gestational Age Birth: A Systematic Review and Meta-Analysis. PLoS One 2015; 10:e0135192. [PMID: 26247870 PMCID: PMC4527773 DOI: 10.1371/journal.pone.0135192] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2015] [Accepted: 07/19/2015] [Indexed: 02/03/2023] Open
Abstract
Background Oxidative stress in preeclampsia and small for gestational age (SGA) birth suggests antioxidant supplementation could prevent these conditions. However, it remains unclear whether maternal antioxidant levels are systematically lower in these pregnancies. Objective To conduct a systematic review of the association between maternal antioxidant levels during pregnancy and preeclampsia or SGA. Methods We searched PubMed, Embase, and several other databases from 1970–2013 for observational studies that measured maternal blood levels of non-enzymatic antioxidants (vitamins A, C, E, and carotenoids) during pregnancy or within 72 hours of delivery. The entire review process was done in duplicate. Study quality was assessed using the Newcastle-Ottawa Scale and additional questions. We pooled the standardized mean difference (SMD) across studies, stratified by outcome and pregnancy trimester, and investigated heterogeneity using meta-regression. Results We reviewed 1,882 unique citations and 64 studies were included. Most studies were small with important risk of bias. Among studies that addressed preeclampsia (n = 58) and SGA (n = 9), 16% and 66%, respectively, measured levels prior to diagnosis. The SMDs for vitamins A, C, and E were significantly negative for overall preeclampsia, but not for mild or severe preeclampsia subtypes. Significant heterogeneity was observed in all meta-analyses and most could not be explained. Evidence for lower carotenoid antioxidants in preeclampsia and SGA was limited and inconclusive. Publication bias appears likely. Conclusions Small, low-quality studies limit conclusions that can be drawn from the available literature. Observational studies inconsistently show that vitamins C and E or other antioxidants are lower in women who develop preeclampsia or SGA. Reverse causality remains a possible explanation for associations observed. New clinical trials are not warranted in light of this evidence; however, additional rigorous observational studies measuring antioxidant levels before clinical detection of preeclampsia and SGA may clarify whether levels are altered at a causally-relevant time of pregnancy.
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Affiliation(s)
- Jacqueline M. Cohen
- Department of Epidemiology, Biostatistics and Occupational Health, McGill University, Montreal, Quebec, Canada
- Centre for Clinical Epidemiology, Lady Davis Institute for Medical Research, Jewish General Hospital, Montreal, Quebec, Canada
- * E-mail:
| | - Margaret Beddaoui
- Centre for Clinical Epidemiology, Lady Davis Institute for Medical Research, Jewish General Hospital, Montreal, Quebec, Canada
| | - Michael S. Kramer
- Department of Epidemiology, Biostatistics and Occupational Health, McGill University, Montreal, Quebec, Canada
- Department of Pediatrics, McGill University, Montreal, Quebec, Canada
| | - Robert W. Platt
- Department of Epidemiology, Biostatistics and Occupational Health, McGill University, Montreal, Quebec, Canada
- Department of Pediatrics, McGill University, Montreal, Quebec, Canada
| | - Olga Basso
- Department of Epidemiology, Biostatistics and Occupational Health, McGill University, Montreal, Quebec, Canada
- Department of Obstetrics and Gynecology, McGill University, Montreal, Quebec, Canada
| | - Susan R. Kahn
- Department of Epidemiology, Biostatistics and Occupational Health, McGill University, Montreal, Quebec, Canada
- Centre for Clinical Epidemiology, Lady Davis Institute for Medical Research, Jewish General Hospital, Montreal, Quebec, Canada
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Abstract
BACKGROUND Preterm birth is a common, costly and dangerous pregnancy complication. Seasonality of risk would suggest modifiable causes. METHODS We examine seasonal effects on preterm birth, using data from the Medical Birth Registry of Norway (2,321,652 births), and show that results based on births are misleading and a fetuses-at-risk approach is essential. In our harmonic-regression Cox proportional hazards model we consider fetal risk of birth between 22 and 37 completed weeks of gestation. We examine effects of both day of year of conception (for early effects) and day of ongoing gestation (for seasonal effects on labour onset) as modifiers of gestational-age-based risk. RESULTS Naïve analysis of preterm rates across days of birth shows compelling evidence for seasonality (P < 10(-152)). However, the reconstructed numbers of conceptions also vary with season (P < 10(-307)), confounding results by inducing seasonal variation in the age distribution of the fetal population at risk. When we instead properly treat fetuses as the individuals at risk, restrict analysis to pregnancies with relatively accurate ultrasound-based assessment of gestational age (available since 1998) and adjust for socio-demographic factors and maternal smoking, we find modest effects of both time of year of conception and time of year at risk, with peaks for early preterm near early January and early July. CONCLUSIONS Analyses of seasonal effects on preterm birth are demonstrably vulnerable to confounding by seasonality of conception, measurement error in conception dating, and socio-demographic factors. The seasonal variation based on fetuses reveals two peaks for early preterm, coinciding with New Year's Day and the early July beginning of Norway's summer break, and may simply reflect a holiday-related pattern of unintended conception.
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Affiliation(s)
- Clarice R Weinberg
- National Institute of Environmental Health Sciences, Research Triangle Park, NC, USA,
| | - Min Shi
- National Institute of Environmental Health Sciences, Research Triangle Park, NC, USA
| | - Lisa A DeRoo
- Department of Global Public Health and Primary Care, University of Bergen, and Medical Birth Registry of Norway, Bergen, Norway and
| | - Olga Basso
- Department of Obstetrics and Gynecology, and Department of Epidemiology, Biostatistics and Occupational Health, McGill University, Montreal, QC, Canada
| | - Rolv Skjærven
- Department of Global Public Health and Primary Care, University of Bergen, and Medical Birth Registry of Norway, Bergen, Norway and
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