The Safety of Low-Dose Aspirin on the Mode of Delivery: Secondary Analysis of the Effect of Aspirin in Gestation and Reproduction Randomized Controlled Trial

OBJECTIVE

This study aimed to examine whether prenatal low-dose aspirin (LDA) therapy affects risk of cesarean versus vaginal delivery.

STUDY DESIGN

This study is a secondary analysis of the randomized clinical effects of aspirin in gestation and reproduction (EAGeR) trial. Women received 81-mg daily aspirin or placebo from preconception to 36 weeks of gestation. Mode of delivery and obstetric complications were abstracted from records. Log-binomial regression models estimated relative risk (RR) of cesarean versus vaginal delivery. Data were analyzed among the total preconception cohort, as well as restricted to women who had a live birth.

RESULTS

Among 1,228 women, 597 had a live birth. In the intent-to-treat analysis, preconception-initiated LDA was not associated with risk of cesarean (RR = 1.02; 95% confidence interval [CI]: 0.98-1.07) compared with placebo. Findings were similar in just women with a live birth and when accounting prior cesarean delivery and parity.

CONCLUSION

Preconception-initiated daily LDA was not associated with mode of delivery among women with one to two prior losses.

KEY POINTS

· Aspirin was not associated with risk of cesarean section.. · Aspirin was not associated with mode of delivery.. · No increased risk of bleeding with use of aspirin..

A Data-Based Approach to Evaluating Representation by Gender and Affiliation in Key Presentation Formats at the Annual Meeting of the Society for Epidemiologic Research

The annual meeting of the Society for Epidemiologic Research (SER) is a major forum for sharing new research and promoting the career development of participants. Because of this, evaluating representation in key presentation formats is critical. For the 3,257 presentations identified at the 2015-2017 SER annual meetings, we evaluated presenter characteristics, including gender, affiliation, subject area, and h-index, and representation in 3 highlighted presentation formats: platform talks (n = 382), invited symposium talks (n = 273), and chairing a concurrent contributed session or symposium (n = 188). Data were abstracted from SER records, abstract booklets, and programs. Gender was assessed using GenderChecker software, and h-index was determined using the Scopus application programming interface. Log-binomial models were adjusted for participant characteristics and conference year. In adjusted models, women were less likely than men to present an invited symposium talk (relative risk = 0.60, 95% confidence interval: 0.45, 0.81) compared with all participants with accepted abstracts. Researchers from US public universities, US government institutions, and international institutions were less likely to present a symposium talk or to chair a concurrent contributed session or symposium than were researchers from US private institutions. The research areas that were most represented in platform talks were epidemiologic methods, social epidemiology, and cardiovascular epidemiology. Our findings suggest differences in representation by gender, affiliation, and subject area after accounting for h-index.

Markers of vitamin D metabolism and premenstrual symptoms in healthy women with regular cycles

STUDY QUESTION

Are insufficient 25-hydroxyvitamin D (25(OH)D) concentrations, and other markers of vitamin D metabolism, associated with premenstrual symptoms in healthy women with regular menstrual cycles?

SUMMARY ANSWER

25(OH)D insufficiency was associated with specific physical premenstrual symptoms, while no associations were observed with psychological symptoms or with other markers of vitamin D metabolism.

WHAT IS KNOWN ALREADY

Prior studies evaluating vitamin D and premenstrual symptoms have yielded mixed results, and it is unknown whether 25(OH)D insufficiency and other markers of vitamin D metabolism are associated with premenstrual symptoms.

STUDY DESIGN, SIZE, DURATION

We used two cohorts of women with regular menstrual cycles; 1191 women aged 18-40 years in EAGeR (cross-sectional analysis of a prospective cohort within a randomized trial) and 76 women aged 18-44 years in BioCycle (prospective cohort). In EAGeR, premenstrual symptoms over the previous year were assessed at baseline, whereas in BioCycle, symptoms were assessed prospectively at multiple points over two menstrual cycles with symptoms queried over the previous week. In both cohorts, symptomatology was assessed via questionnaire regarding presence and severity of 14 physical and psychological symptoms the week before and after menses. Both studies measured 25(OH)D in serum. We also evaluated the association of additional markers of vitamin D metabolism and calcium homeostasis, including intact parathyroid hormone (iPTH), calcium (Ca), fibroblast growth factor 23 (FGF23), and 1,25 dihydroxyvitamin D (1,25(OH)2D) with premenstrual symptoms in the BioCycle cohort.

PARTICIPANTS/MATERIALS, SETTING, METHODS

One cohort of women actively seeking pregnancy (Effects of Aspirin in Gestation and Reproduction (EAGeR)) and one cohort not seeking pregnancy (BioCycle) were evaluated. Log-binomial regression was used to estimate risk ratios (RR) and 95% CIs for associations between insufficient 25(OH)D (<30 ng/ml) and individual premenstrual symptoms, adjusting for age, BMI, race, smoking, income, physical activity, and season of blood draw.

MAIN RESULTS AND THE ROLE OF CHANCE

25(OH)D insufficiency was associated with increased risk of breast fullness/tenderness (EAGeR RR 1.27, 95% CI 1.03, 1.55; BioCycle RR 1.37, 95% CI 0.56, 3.32) and generalized aches and pains (EAGeR RR 1.33, 95% CI 1.01, 1.78; BioCycle 1.36, 95% CI 0.41, 4.45), though results were imprecise in the BioCycle study. No associations were observed between insufficient 25(OH)D and psychological symptoms in either cohort. In BioCycle, iPTH, Ca, FGF23, and 1,25(OH) 2D were not associated with any premenstrual symptoms.

LIMITATIONS, REASONS FOR CAUTION

Results from the EAGeR study were limited by the study design, which assessed both 25(OH)D at baseline and individual premenstrual symptoms over the past year at the baseline. As such, reverse causality is a potential concern. Though premenstrual symptoms were assessed prospectively in the BioCycle cohort, the power was limited due to small sample size. However, results were fairly consistent across both studies.

WIDER IMPLICATIONS OF THE FINDINGS

Serum 25(OH)D may be associated with risk and severity of specific physical premenstrual symptoms.

STUDY FUNDING/COMPETING INTEREST(S)

This work was supported by the Intramural Research Program of the Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland (Contract nos. HHSN267200603423, HHSN267200603424, and HHSN267200603426). JG.R. and D.L.K. have been funded by the NIH Medical Research Scholars Program, a public-private partnership jointly supported by the NIH and generous contributions to the Foundation for the NIH by the Doris Duke Charitable Foundation (Grant #2014194), the American Association for Dental Research, the Colgate Palmolive Company, Genentech, and other private donors. For a complete list, visit the foundation website at http://www.fnih.org. The authors have no conflicts of interest to disclose.

TRIAL REGISTRATION NUMBER

Clinicaltrials.gov NCT00467363.

Cannabis use while trying to conceive: a prospective cohort study evaluating associations with fecundability, live birth and pregnancy loss

STUDY QUESTION

Is cannabis use assessed via urinary metabolites and self-report during preconception associated with fecundability, live birth and pregnancy loss?

SUMMARY ANSWER

Preconception cannabis use was associated with reduced fecundability among women with a history of pregnancy loss attempting pregnancy despite an increased frequency of intercourse.

WHAT IS KNOWN ALREADY

Cannabis use continues to rise despite limited evidence of safety during critical windows of pregnancy establishment. While existing studies suggest that self-reported cannabis use is not associated with fecundability, self-report may not be reliable.

STUDY DESIGN, SIZE, DURATION

A prospective cohort study was carried out including 1228 women followed for up to six cycles while attempting pregnancy (2006 to 2012), and throughout pregnancy if they conceived.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Women aged 18-40 years with a history of pregnancy loss (n = 1228) were recruited from four clinical centers. Women self-reported preconception cannabis use at baseline and urinary tetrahydrocannabinol metabolites were measured throughout preconception and early pregnancy (up to four times during the study: at baseline, after 6 months of follow-up or at the beginning of the conception cycle, and weeks 4 and 8 of pregnancy). Time to hCG-detected pregnancy, and incidence of live birth and pregnancy loss were prospectively assessed. Fecundability odds ratios (FOR) and 95% CI were estimated using discrete time Cox proportional hazards models, and risk ratios (RRs) and 95% CI using log-binomial regression adjusting for age, race, BMI, education level, baseline urine cotinine, alcohol use and antidepressant use.

MAIN RESULTS AND THE ROLE OF CHANCE

Preconception cannabis use was 5% (62/1228), based on combined urinary metabolite measurements and self-report, and 1.3% (11/789) used cannabis during the first 8 weeks of gestation based on urinary metabolites only. Women with preconception cannabis use had reduced fecundability (FOR 0.59; 95% CI 0.38, 0.92). Preconception cannabis use was also associated with increased frequency of intercourse per cycle (9.4 ± 7 versus 7.5 ± 7 days; P = 0.02) and higher LH (percentage change 64%, 95% CI 3, 161) and higher LH:FSH ratio (percentage change 39%, 95% CI 7, 81). There were also suggestive, though imprecise, associations with anovulation (RR 1.92, 95% CI 0.88, 4.18), and live birth (42% (19/45) cannabis users versus 55% (578/1043) nonusers; RR 0.80, 95% CI 0.57, 1.12). No associations were observed between preconception cannabis use and pregnancy loss (RR 0.81, 95% CI 0.46, 1.42). Similar results were observed after additional adjustment for parity, income, employment status and stress. We were unable to estimate associations between cannabis use during early pregnancy and pregnancy loss due to limited sample size.

LIMITATIONS, REASONS FOR CAUTION

Owing to the relatively few cannabis users in our study, we had limited ability to make conclusions regarding live birth and pregnancy loss, and were unable to account for male partner use. While results were similar after excluding smokers, alcohol use and any drug use in the past year, some residual confounding may persist due to these potential co-exposures.

WIDER IMPLICATIONS OF THE FINDINGS

These findings highlight potential risks on fecundability among women attempting pregnancy with a history of pregnancy loss and the need for expanded evidence regarding the reproductive health effects of cannabis use in the current climate of increasing legalization.

STUDY FUNDING/COMPETING INTEREST(S)

This work was supported by the Intramural Research Program of the Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland (Contract numbers: HHSN267200603423, HHSN267200603424, HHSN267200603426, HHSN275201300023I). Jeannie G. Radoc has been funded by the National Institutes of Health Medical Research Scholars Program, a public-private partnership supported jointly by the National Institutes of Health and generous contributions to the Foundation for the National Institutes of Health from the Doris Duke Charitable Foundation (DDCF Grant # 2014194), Genentech, Elsevier, and other private donors. The authors report no conflict of interest in this work and have nothing to disclose.

TRIAL REGISTRATION NUMBER

Clinicaltrials.gov NCT00467363.

Associations between blood cadmium and endocrine features related to PCOS-phenotypes in healthy women of reproductive age: a prospective cohort study

BACKGROUND

Cadmium is an endocrine disrupting chemical that affects the hypothalamic-pituitary-gonadal axis. Though evidence suggests its potential role in altering androgen synthesis and metabolic pathways that are characteristic of polycystic ovary syndrome (PCOS), its relation in healthy women of reproductive age is largely unknown. As women with mild sub-clinical features of PCOS who do not meet the diagnostic criteria of PCOS may still experience reduced fecundability, investigating associations between cadmium and PCOS-phenotypes among healthy women may provide unique insight into the reproductive implications for many on the PCOS spectrum. Therefore, the objective of this study was to evaluate associations between cadmium and androgens, anti-Müllerian hormone (AMH), and metabolic markers in women of reproductive age.

METHODS

This was a prospective cohort study of 251 healthy premenopausal women without self-reported PCOS (mean age 27.3 years and BMI 24.1 kg/m²). Cadmium was measured in blood collected at baseline. Reproductive hormones and metabolic markers were measured in fasting serum 8 times per menstrual cycle for 2 cycles. Linear mixed models and Poisson regression with a robust error variance were used to examine associations between cadmium and reproductive hormones and metabolic markers and anovulation, respectively.

RESULTS

Median (interquartile range) blood cadmium concentrations at baseline were 0.30 (0.19-0.43) µg/L. Higher levels of testosterone (2.2 %, 95 % confidence interval [CI] 0.4, 4.1), sex hormone-binding globulin (2.9 %, 95 % CI 0.5, 5.5), and AMH (7.7 %, 95 % CI 1.1, 14.9) were observed per 0.1 µg/L increase in cadmium concentrations. An 18 % higher probability of a mild PCOS-phenotype (95 % CI 1.06, 1.31), defined by a menstrual cycle being in the highest quartile of cycle-averaged testosterone and AMH levels, was also found per 0.1 µg/L increase in cadmium levels. No associations were observed for insulin and glucose. These findings were consistent even after analyses were restricted to non-smokers or further adjusted for dietary factors to account for potential sources of exposure.

CONCLUSIONS

Overall, among healthy reproductive-aged women, cadmium was associated with endocrine features central to PCOS, but not with metabolic markers. These suggest its potential role in the hormonal milieu associated with PCOS even at low levels of exposure.

The role of maternal preconception vitamin D status in human offspring sex ratio

Evolutionary theory suggests that some animal species may experience shifts in their offspring sex ratio in response to maternal health and environmental conditions, and in some unfavorable conditions, females may be less likely to bear sons. Experimental data in both animals and humans indicate that maternal inflammation may disproportionately impact the viability of male conceptuses; however, it is unknown whether other factors associated with both pregnancy and inflammation, such as vitamin D status, are associated with the offspring sex ratio. Here, we show that among 1,228 women attempting pregnancy, preconception 25-hydroxyvitamin D concentrations are positively associated with the live birth of a male infant, with notably stronger associations among women with elevated high sensitivity C-reactive protein, a marker of systemic low-grade inflammation. Our findings suggest that vitamin D may mitigate maternal inflammation that would otherwise be detrimental to the implantation or survival of male conceptuses in utero.

Urinary selective serotonin reuptake inhibitors across critical windows of pregnancy establishment: a prospective cohort study of fecundability and pregnancy loss

OBJECTIVE

To prospectively investigate the association of selective serotonin reuptake inhibitor (SSRI) exposure through critical windows of pregnancy establishment with fecundability and pregnancy loss.

DESIGN

Prospective cohort study using longitudinal urine measurements of common SSRIs while women are actively trying to conceive.

SETTING

Four clinical sites.

PATIENT(S)

A total of 1,228 women without uncontrolled depression/anxiety, attempting natural conception while participating in a randomized trial of preconception-initiated low-dose aspirin.

INTERVENTIONS(S)

Not applicable.

MAIN OUTCOME MEASURE(S)

Urinary SSRIs (fluoxetine, sertraline, escitalopram/citalopram) were measured while trying to conceive and, for women who became pregnant, at weeks 0, 4, and 8 of pregnancy. Fecundability odds ratios and incidence of pregnancy loss and live birth were estimated.

RESULT(S)

A total of 172 women (14%) were exposed to SSRIs while trying to conceive. SSRI exposure was associated with 24% reduced fecundability, and accordingly, a nonsignificant 9% lower live birth incidence, with significantly lower live birth in fluoxetine-exposed women. SSRI exposure was not associated with subsequent pregnancy loss, whether exposure was before conception or at 0, 4, or 8 weeks of gestation, although estimates varied by specific SSRI drug.

CONCLUSION(S)

Women using SSRIs may have more difficulty becoming pregnant, and although SSRI exposure overall was not associated with pregnancy loss, fluoxetine deserves caution and future study.

CLINICAL TRIAL REGISTRATION NUMBER

NCT00467363.

Maternal fatty acid concentrations and newborn DNA methylation

BACKGROUND

Preconception nutrition sets the stage for a healthy pregnancy. Maternal fatty acids (FAs) are related to beneficial neonatal outcomes with DNA methylation proposed as a mechanism; however, few studies have investigated this association and none with preconception FAs.

OBJECTIVES

We examined the relations of maternal plasma FA concentrations at preconception (n = 346) and 8 weeks of gestation (n = 374) with newborn DNA methylation.

METHODS

The Effects of Aspirin in Gestation and Reproduction Trial (2006-2012) randomly assigned women with previous pregnancy loss to low dose aspirin or placebo prior to conception. We measured maternal plasma phospholipid FA concentration at preconception (on average 4 mo before pregnancy) and 8 weeks of gestation. Cord blood DNA from singletons was measured using the MethylationEPIC BeadChip. We used robust linear regression to test the associations of FA concentration with methylation β-values of each CpG site, adjusting for estimated cell count using a cord blood reference, sample plate, maternal sociodemographic characteristics, cholesterol, infant sex, and epigenetic-derived ancestry. False discovery rate correction was used for multiple testing.

RESULTS

Mean ± SD concentrations of preconception marine (20:5n-3+22:6n-3+22:5n-3) and ω-6 PUFAs, SFAs, MUFAs, and trans FAs were 4.7 ± 1.2, 38.0 ± 2.0, 39.4 ± 1.8, 11.6 ± 1.1, and 1.0 ± 0.4 % of total FA, respectively; concentrations at 8 weeks of gestation were similar. Preconception marine PUFA concentration was associated with higher methylation at GRAMD2 (P = 1.1 × 10-8), LOXL1 (P = 5.5 × 10-8), SIK3 (P = 1.6 × 10-7), HTR1B (P = 1.9 × 10-7), and MCC (P = 2.1 × 10-7) genes. Preconception SFA concentration was associated with higher methylation at KIF25-AS1 and lower methylation at SLC39A14; other associations exhibited sensitivity to outliers. The trans FA concentration was related to lower methylation at 3 sites and higher methylation at 1 site. FAs at 8 weeks of gestation were largely unrelated to DNA methylation.

CONCLUSIONS

Maternal preconception FAs are related to newborn DNA methylation of specific CpG sites, highlighting the importance of examining nutritional exposures preconceptionally. This trial was registered at clinicaltrials.gov as NCT00467363.

Assessing Representation and Perceived Inclusion among Members in the Society for Epidemiologic Research

Using web-based survey data collected June - August 2018 from the Society for Epidemiologic Research (SER) members, we characterized numerous dimensions of social identity and lived experience, and assessed relationships between these characteristics and perceptions of inclusion and society participation. We quantified associations between characteristics, feeling very welcomed, high (top 25th percentile) self-initiated participation, and any (top 10th percentile) society-initiated participation. Racial/ethnic and religious minority categories were blinded to preserve anonymity and we accounted for missing data. Most 2018 SER members (n = 1631) were white (62%) or female (66%). Females with racial/ethnic non-response were least likely, while white males were most likely to report feeling very welcomed. Members who did not report race, identified with a specific racial/ethnic minority, or were politically conservative/right-leaning were less likely than white or liberal/left-leaning members to have high self-initiated participation. Women and individuals of a specific racial/ethnic minority or minority religious affiliations were less likely to participate in events initiated by the society. These data represent a baseline for assessing trends and the impact of future initiatives aimed at improving diversity, inclusion, representation and participation within SER.

Urinary Phytoestrogens and Relationship to Menstrual Cycle Length and Variability Among Healthy, Eumenorrheic Women

Context

Phytoestrogens may influence fecundability, although biological mechanisms remain elusive. Since it is hypothesized that phytoestrogens may act through influencing hormone levels, we investigated associations between phytoestrogens and menstrual cycle length, a proxy for the hormonal milieu, in healthy women attempting pregnancy.

Design

A population-based prospective cohort of 326 women ages 18 to 40 with self-reported cycles of 21 to 42 days were followed until pregnancy or for 12 months of attempting pregnancy.

Methods

Urinary genistein, daidzein, O-desmethylangolensin, equol, enterodiol, and enterolactone were measured upon enrollment. Cycle length was determined from fertility monitors and daily journals. Linear mixed models assessed associations with continuous cycle length and were weighted by the inverse number of observed cycles. Logistic regression models assessed menstrual regularity (standard deviation > 75th vs ≤ 75th percentile). Models were adjusted for age, body mass index, race, creatinine, exercise, supplements, lipids, lead, cadmium, cotinine, parity, alcohol, and other phytoestrogens.

Results

Individual phytoestrogens were not associated with cycle length, although total phytoestrogens were associated with shorter cycles (-0.042 days; 95% confidence interval [CI], -0.080 to -0.003, per 10% increase). Each 1 nmol/L increase in enterolactone (odds ratio [OR] 0.88; 95% CI, 0.79-0.97) and total lignans (OR 0.85; 95% CI, 0.76-0.95) was associated with reduced irregularity, and each 1 nmol/L increase in genistein with irregularity (OR 1.19; 95% CI, 1.02-1.38).

Conclusion

Phytoestrogens were not meaningfully associated with cycle length but may be associated with menstrual regularity, among women with self-reported regular cycles. These results highlight differences between isoflavones and lignans and are reassuring for women attempting pregnancy.

Preconception Leptin and Fecundability, Pregnancy, and Live Birth Among Women With a History of Pregnancy Loss

Context

With the increase of obesity, it is imperative to understand the neuroendocrine mechanisms, including the neuroendocrine hormone leptin, by which obese or overweight women are at increased risk for subfertility and infertility.

Objective

The objective was to examine associations between preconception serum leptin concentrations, fecundability, pregnancy, and live birth.

Design

Secondary analysis of a prospective cohort among women with prior pregnancy losses.

Setting

The study was conducted at four US medical centers (2006 to 2012).

Intervention

Not available.

Materials and Methods

Preconception serum leptin concentrations were measured at baseline, and women were followed for up to six menstrual cycles, and throughout pregnancy if they conceived. Discrete Cox proportional hazard regression models were used to assess fecundability odds ratios (FORs) and log-binomial regression to estimate risk ratios (RRs) for pregnancy and live birth. Models were adjusted for age, physical activity, treatment arm, and adiposity, either by measured waist-to-hip ratio or body mass index (BMI).

Results

High leptin concentrations were associated with decreased fecundability (FOR 0.72, 95% CI 0.58, 0.90), reduced risk of pregnancy (RR 0.87, 95% CI 0.78, 0.96) and live birth (RR 0.76, 95% CI 0.65, 0.89) comparing the upper to the lower tertile. However, adjustment for BMI in lieu of waist-to-hip ratio nullified observed associations.

Conclusions

In women with a history of pregnancy loss, relations between higher preconception leptin and fecundability were attenuated after adjustment for BMI, although not after adjustment for other markers of adiposity. Leptin may serve as a complementary marker of adiposity for assessment of obesity and reproductive outcomes.

Pilot randomized trial of short-term changes in inflammation and lipid levels during and after aspirin and pravastatin therapy

BACKGROUND

Inflammation and elevated blood lipids are associated with infertility. Aspirin and statin therapy may improve infertility treatment outcomes among overweight and obese women with systemic inflammation, but little is known about the short-term effects of statins in this population. We conducted a pilot study of aspirin, pravastatin, or combined treatment among a group of overweight and obese, reproductive-aged women. Our goal was to characterize short-term changes in inflammatory and lipid biomarkers during and after treatment.

METHODS

In this open-label trial, women aged 18-40 years with a body mass index ≥25 kg/m² were randomized to receive either 162 mg aspirin, 40 mg pravastatin, or both. The study medication was taken daily for 2 weeks, and participants were then followed for a two-week washout period. Participants provided blood samples at baseline, after the intervention period, and after the washout period. The outcomes were changes in biomarkers of inflammation and lipids measured in blood components at each timepoint.

RESULTS

Nine, 8, and 8 women were randomized to the aspirin, pravastatin, and combined arms, respectively. Analyses were conducted among 8, 7, and 7 women in the aspirin, pravastatin, and combined arms for whom biomarker data was available at baseline. High-sensitivity C-reactive protein (hsCRP) levels were lower after treatment in all arms and continued to decrease after washout in the pravastatin and combined arms. Results were consistent between the whole sample and women with baseline hsCRP between 2 and 10 mg/L. Low-density lipoprotein (LDL) cholesterol was lower after treatment in the pravastatin and combined arms and rose slightly after washout.

CONCLUSIONS

Our results provide preliminary evidence that short-term aspirin and pravastatin therapy reduces hsCRP and LDL cholesterol among overweight and obese women of reproductive age, including those with low-grade inflammation. Because of these short-term effects, these drugs may improve infertility treatment outcomes in this population, which we will assess in a future randomized trial.