Data Resource Profile: Better Outcomes Registry & Network (BORN) Ontario

Associations of neighborhood greenspace, and active living environments with autism spectrum disorders: A matched case-control study in Ontario, Canada

BACKGROUND

Increasing evidence links early life residential exposure to natural urban environmental attributes and positive health outcomes in children. However, few studies have focused on their protective effects on the risk of autism spectrum disorder (ASD). The aim of this study was to investigate the associations of neighborhood greenspace, and active living environments during pregnancy with ASD in young children (≤6 years).

METHODS

We conducted a population-based matched case-control study of singleton term births in Ontario, Canada for 2012-2016. The ASD and environmental data was generated using the Ontario Autism Spectrum Profile, the Better Outcomes Registry & Network Ontario, and Canadian Urban Environmental Health Research Consortium. We employed conditional logistic regressions to estimate the odds ratio (OR) between ASD and environmental factors characterizing selected greenspace metrics and neighborhoods conducive to active living (i.e., green view index (GVI), normalized difference vegetation index (NDVI), tree canopy, park proximity and active living environments index (ALE)).

RESULTS

We linked 8643 mother-child pairs, including 1554 cases (18%). NDVI (OR 1.034, 0.944-1.024, per Inter Quartile Range [IQR] = 0.08), GVI (OR 1.025, 95% CI 0.953-1.087, per IQR = 9.45%), tree canopy (OR 0.992, 95% CI 0.903-1.089, per IQR = 6.24%) and the different categories of ALE were not associated with ASD in adjusted models for air pollution. In contrast, living closer to a park was protective (OR 0.888, 0.833-0.948, per 0.06 increase in park proximity index), when adjusted for air pollution.

CONCLUSIONS

This study reported mixed findings showing both null and beneficial effects of green spaces and active living environments on ASD. Further investigations are warranted to elucidate the role of exposure to greenspaces and active living environments on the development of ASD.

Changes associated with the COVID-19 pandemic on postpartum screening results in Ontario, Canada: The healthy babies healthy children screening tool

BACKGROUND

Research on the impact of the COVID-19 pandemic on mothers/childbearing parents has mainly been cross-sectional and focused on psychological symptoms. This study examined the impact on function using ongoing, systematic screening of a representative Ontario sample.

METHODS

An interrupted time series analysis of repeated cross-sectional data from a province-wide screening program using the Healthy Babies Healthy Children (HBHC) tool assessed changes associated with the pandemic at the time of postpartum discharge from hospital. Postal codes were used to link to neighborhood-level data. The ability to parent or care for the baby/child and other psychosocial and behavioral outcomes were assessed.

RESULTS

The co-primary outcomes of inability to parent or care for the baby/child were infrequently observed in the pre-pandemic (March 9, 2019-March 15, 2020) and initial pandemic periods (March 16, 2020-March 23, 2021) (parent 209/63,006 (0.33%)-177/56,117 (0.32%), care 537/62,955 (0.85%)-324/56,086 (0.58%)). Changes after pandemic onset were not observed for either outcome although a significant (p = 0.02) increase in slope was observed for inability to parent (with questionable clinical significance). For secondary outcomes, worsening was only seen for reported complications during labor/delivery. Significant improvements were observed in the likelihood of being unable to identify a support person to assist with care, need of newcomer support, and concerns about money over time.

CONCLUSIONS

There were no substantive changes in concerns about ability to parent or care for children. Adverse impacts of the pandemic may have been mitigated by accommodations for remote work and social safety net policies.

Outcomes associated with planned place of birth among low-risk pregnancies in Ontario, Canada (2012-2021): A protocol for a population-based propensity score weighted cohort study

BACKGROUND

Evidence suggests that for low-risk pregnancies, planned home births attended by a skilled health professional in settings where such services are well integrated are associated with lower risk of intrapartum interventions and no increase in adverse health outcomes. Monitoring and updating evidence on the safety of planned home births is necessary to inform ongoing clinical and policy decisions.

METHODS

This protocol describes a population-based retrospective cohort study which aims to compare risk of (a) neonatal morbidity and mortality, and (b) maternal outcomes and birth interventions, between people at low obstetrical risk with a planned home birth with a midwife, a planned a hospital birth with a midwife, or a planned hospital birth with a physician. The study population will include Ontario residents who gave birth in Ontario, Canada between April 1, 2012, and March 31, 2021. We will use data collected prospectively in a provincial perinatal data registry. The primary outcome will be severe neonatal morbidity or mortality, a composite binary outcome that includes one or more of the following conditions: stillbirth during the intrapartum period, neonatal death (death of a liveborn infant in the first 28 completed days of life), five-minute Apgar score <4, or infant resuscitation requiring cardiac compressions. We will conduct a stratified analysis with three strata: nulliparous, parous-no previous caesarean birth, and parous-prior caesarean birth. To reduce the impact of selection bias in estimating the effect of planned place of birth on neonatal and maternal outcomes, we will use propensity score (PS) overlap weighting (OW) and modified Poisson regression to conduct multivariate analyses.

Development and validation of interprofessional health education module for the management of gestational diabetes mellitus

BACKGROUND

Gestational diabetes mellitus (GDM) is a glucose intolerance that shows its first onset during pregnancy. In India, GDM affects as many as 5 million women annually. The interprofessional collaborative educational intervention is crucial for GDM management. This study illustrates the collaborative effort in developing and validating an interprofessional health education module designed for healthcare professionals during consultation sessions with GDM patients.

MATERIALS AND METHODS

The investigation involved three stages: 1) needs assessment for module contents and objectives, 2) health education module development by an interprofessional team, and 3) module validation. We received ethics approval from the institution's ethics committee.

RESULTS

The interprofessional team developed and validated the evidence-based English-printed module. The module had 27 units and covered six topics: an introduction to GDM and its management, dietary recommendations for GDM, exercise, yoga recommendations for GDM, weight control, and postpartum care.

CONCLUSION

The interprofessional team developed the educational module, wherein there is an integration of the domains of exercise and yoga along with medicines and nutrition therapy. The module was developed based on local requirements and evidence-based practices. Healthcare professionals can use the interprofessional health education module when advising diabetic pregnant patients.

Infant Infections Following Cesarean Delivery on Maternal Request: A Population-Based Cohort Study

OBJECTIVES

Investigations about cesarean delivery (CD) on maternal request (CDMR) and infant infection risk frequently rely on administrative data with poorly defined indications for CD. We sought to determine the association between CDMR and infant infection using an intent-to-treat approach.

METHODS

This was a population-based cohort study of low-risk singleton pregnancies with a term live birth in Ontario, Canada between April 2012 and March 2018. Subjects with prior CD were excluded. Outcomes included upper and lower respiratory tract infections, gastrointestinal infections, otitis media, and a composite of these 4. Relative risk and 95% CI were calculated for component and composite outcomes up to 1 year following planned CDMR versus planned vaginal deliveries (VDs). Subgroup and sensitivity analyses included age at infection (≤28 vs. >28 days), type of care (ambulatory vs. hospitalisation), restricting the cohort to nulliparous pregnancies, and including individuals with previous CD. Last, we re-examined outcome risk on an as-treated basis (actual CD vs. actual VD).

RESULTS

Of 422 134 pregnancies, 0.4% (1827) resulted in a planned CDMR. After adjusting for covariates, planned CDMR was not associated with a risk of composite infant infections (adjusted relative risk 1.02; 95% CI 0.92-1.11). Findings for component infection outcomes, subgroup, and sensitivity analyses were similar. However, the as-treated analysis of the role of delivery mode on infant risk for infection demonstrated that actual CD (planned and unplanned) was associated with an increased risk for infant infections compared to actual VD.

CONCLUSIONS

Planned CDMR is not associated with increased risk for neonatal or infant infections compared with planned VD. Study design must be carefully considered when investigating the impact of CDMR on infant infection outcomes.

Postpartum Emergency Department Use Following Midwifery-Model vs Obstetrics-Model Care

Importance

Emergency department (ED) use postpartum is a common and often-preventable event. Unlike traditional obstetrics models, the Ontario midwifery model offers early care postpartum.

Objective

To assess whether postpartum ED use differs between women who received perinatal care in midwifery-model care vs in traditional obstetrics-model care.

Design, Setting, and Participants

This retrospective population-based cohort study took place in Ontario, Canada, where public health care is universally funded. Participants included women who were low risk and primiparous and gave birth to a live baby in an Ontario hospital between 2012 and 2018. Data were collected from April 2012 to March 2018 and analyzed from June 2022 to April 2023.

Exposures

Perinatal care clinician, namely, a midwife or obstetrician.

Main Outcome and Measures

: Any unscheduled ED visit 42 days postpartum or less. Poisson regression models compared ED use between women with midwifery-model care vs obstetrics-model care, weighting by propensity score-based overlap weights.

Results

Among 104 995 primiparous women aged 11 to 50 years, those in midwifery-model care received a median (IQR) of 7 (6-8) postpartum visits, compared with 0 (0-1) visits among those receiving obstetrics-model care. Unscheduled ED visits 42 days or less postpartum occurred for 1549 of 23 124 women (6.7%) with midwifery-model care compared with 6902 of 81 871 women (8.4%) with traditional obstetrics-model care (adjusted relative risks [aRR], 0.78; 95% CI, 0.73-0.83). Similar aRRs were seen in women with a spontaneous vaginal birth (aRR, 0.71; 95% CI, 0.65-0.78) or assisted vaginal birth (aRR, 0.70; 95% CI, 0.59-0.82) but not those with a cesarean birth (aRR, 0.94; 95% CI, 0.86-1.03) or those with intrapartum transfer of care between a midwife and obstetrician (aRR, 0.94; 95% CI, 0.87-1.04). ED use 7 days or less postpartum was also lower among women receiving midwifery model care (aRR, 0.70; 95% CI, 0.65-0.77).

Conclusions and Relevance

In this cohort study, midwifery-model care was associated with less postpartum ED use than traditional obstetrics-model care among women who had low risk and were primiparous, which may be due to early access to postpartum care provided by Ontario midwives.

Sociodemographic Factors and Trends in Bronchiolitis-Related Emergency Department Visit and Hospitalization Rates

Importance

Bronchiolitis is the most common and most cumulatively expensive condition in pediatric hospital care. Few population-based studies have examined health inequalities in bronchiolitis outcomes over time.

Objective

To examine trends in bronchiolitis-related emergency department (ED) visit and hospitalization rates by sociodemographic factors in a universally funded health care system.

Design, Setting, and Participants

This repeated cross-sectional cohort study was performed from April 1, 2004, to March 31, 2022, using population-based health administrative data from children younger than 2 years in Ontario, Canada.

Main Outcome and Measures

Bronchiolitis ED visit and hospitalization rates per 1000 person-years reported for the equity stratifiers of sex, residence location (rural vs urban), and material resources quintile. Trends in annual rates by equity stratifiers were analyzed using joinpoint regression and estimating the average annual percentage change (AAPC) with 95% CI and the absolute difference in AAPC with 95% CI from April 1, 2004, to March 31, 2020.

Results

Of 2 921 573 children included in the study, 1 422 088 (48.7%) were female and 2 619 139 (89.6%) lived in an urban location. Emergency department visit and hospitalization rates were highest for boys, those with rural residence, and those with least material resources. There were no significant between-group absolute differences in the AAPC in ED visits per 1000 person-years by sex (female vs male; 0.22; 95% CI, -0.92 to 1.35; P = .71), residence (rural vs urban; -0.31; 95% CI -1.70 to 1.09; P = .67), or material resources (quintile 5 vs 1; -1.17; 95% CI, -2.57 to 0.22; P = .10). Similarly, there were no significant between-group absolute differences in the AAPC in hospitalizations per 1000 person-years by sex (female vs male; 0.53; 95% CI, -1.11 to 2.17; P = .53), residence (rural vs urban; -0.62; 95% CI, -2.63 to 1.40; P = .55), or material resources (quintile 5 vs 1; -0.93; 95% CI -3.80 to 1.93; P = .52).

Conclusions and Relevance

In this population-based cohort study of children in a universally funded health care system, inequalities in bronchiolitis ED visit and hospitalization rates did not improve over time.

Defining a low-risk birth cohort: a cohort study comparing two perinatal data sets in Ontario, Canada

Introduction

There are two main data sources for perinatal data in Ontario, Canada: the BORN BIS and CIHI-DAD. Such databases are used for perinatal health surveillance and research, and to guide health care related decisions.

Objectives

Our primary objective was to examine the level of agreement between the BIS and CIHI-DAD. Our secondary objectives were to identify the differences between the data sources when identifying a low-risk birth (LRB) cohort and to understand their implications.

Methods

We conducted a population-based cohort study comparing characteristics and clinical outcomes of all linkable births in BIS and CIHI-DAD between 1st April 2012 and 31st March 2018. We excluded out-of-hospital births, those with invalid healthcare numbers, non-Ontario residents and gestational age <20 weeks. We compared the portion of the cohort that met the criteria of a provincial definition of LRB based on each data source and compared clinical outcomes between the groups.

Results

During the study period, 779,979 eligible births were linkable between the two data sources. After applying the LRB exclusions, there were 129,908 cases in the BIS and 136,184 cases in CIHI-DAD. Most exclusion criteria had almost perfect, substantial or moderate agreement. The agreement for non-cephalic presentation and BMI ≥ 40 kg/m2 (kappa coefficients 0.409 and 0.256, respectively) was fair. Comparison between the two LRB cohorts identified differences in the prevalence of cesarean (14.3% BIS versus 12.0% CIHI-DAD) and NICU admission (8.7% BIS versus 7.5% CIHI-DAD) and only 0.01% difference in the prevalence of ICU admission.

Conclusions

Overall, we found high levels of agreement between the BIS and CIHI-DAD. Identifying a LRB cohort in either database may be appropriate, with the caveat of appropriate understanding of the collection, coding and definition of certain outcomes. The decision for selecting a database may depend on which variables are most important in a particular analysis.

Ultrasonographic Fetal Nuchal Translucency Measurements and Cytogenetic Outcomes

Importance

Ultrasonographic measurement of fetal nuchal translucency is used in prenatal screening for trisomies 21 and 18 and other conditions. A cutoff of 3.5 mm or greater is commonly used to offer follow-up investigations, such as prenatal cell-free DNA (cfDNA) screening or cytogenetic testing. Recent studies showed a possible association with chromosomal anomalies for levels less than 3.5 mm, but extant evidence has limitations.

Objective

To evaluate the association between different nuchal translucency measurements and cytogenetic outcomes on a population level.

Design, Setting, and Participants

This population-based retrospective cohort study used data from the Better Outcomes Registry & Network, the perinatal registry for Ontario, Canada. All singleton pregnancies with an estimated date of delivery from September 1, 2016, to March 31, 2021, were included. Data were analyzed from March 17 to August 14, 2023.

Exposures

Nuchal translucency measurements were identified through multiple-marker screening results.

Main Outcomes and Measures

Chromosomal anomalies were identified through all Ontario laboratory-generated prenatal and postnatal cytogenetic tests. Cytogenetic testing results, supplemented with information from cfDNA screening and clinical examination at birth, were used to identify pregnancies without chromosomal anomalies. Multivariable modified Poisson regression with robust variance estimation and adjustment for gestational age was used to compare cytogenetic outcomes for pregnancies with varying nuchal translucency measurement categories and a reference group with nuchal translucency less than 2.0 mm.

Results

Of 414 268 pregnancies included in the study (mean [SD] maternal age at estimated delivery date, 31.5 [4.7] years), 359 807 (86.9%) had a nuchal translucency less than 2.0 mm; the prevalence of chromosomal anomalies in this group was 0.5%. An increased risk of chromosomal anomalies was associated with increasing nuchal translucency measurements, with an adjusted risk ratio (ARR) of 20.33 (95% CI, 17.58-23.52) and adjusted risk difference (ARD) of 9.94% (95% CI, 8.49%-11.39%) for pregnancies with measurements of 3.0 to less than 3.5 mm. The ARR was 4.97 (95% CI, 3.45-7.17) and the ARD was 1.40% (95% CI, 0.77%-2.04%) when restricted to chromosomal anomalies beyond the commonly screened aneuploidies (excluding trisomies 21, 18, and 13 and sex chromosome aneuploidies).

Conclusions and Relevance

In this cohort study of 414 268 singleton pregnancies, those with nuchal translucency measurements less than 2.0 mm were at the lowest risk of chromosomal anomalies. Risk increased with increasing measurements, including measurements less than 3.5 mm and anomalies not routinely screened by many prenatal genetic screening programs.

The impact of isolated obesity compared with obesity and other risk factors on risk of stillbirth: a retrospective cohort study

BACKGROUND

Maternal obesity is associated with stillbirth, but uncertainty persists around the effects of higher obesity classes. We sought to compare the risk of stillbirth associated with maternal obesity alone versus maternal obesity and additional or undiagnosed factors contributing to high-risk pregnancy.

METHODS

We conducted a retrospective cohort study using the Better Outcomes Registry and Network (BORN) for singleton hospital births in Ontario between 2012 and 2018. We used multivariable Cox proportional hazard regression and logistic regression to evaluate the relationship between prepregnancy maternal body mass index (BMI) class and stillbirth (reference was normal BMI). We treated maternal characteristics and obstetrical complications as independent covariates. We performed mediator analyses to measure the direct and indirect effects of BMI on stillbirth through major common-pathway complications. We used fully adjusted and partially adjusted models, representing the impact of maternal obesity alone and maternal obesity with other risk factors on stillbirth, respectively.

RESULTS

We analyzed data on 681 178 births between 2012 and 2018, of which 1956 were stillbirths. Class I obesity was associated with an increased incidence of stillbirth (adjusted hazard ratio [HR] 1.55, 95% confidence interval [CI] 1.35-1.78). This association was stronger for class III obesity (adjusted HR 1.80, 95% CI 1.44-2.24), and strongest for class II obesity (adjusted HR 2.17, 95% CI 1.83-2.57). Plotting point estimates for odds ratios, stratified by gestational age, showed a marked increase in the relative odds for stillbirth beyond 37 weeks' gestation for those with obesity with and without other risk factors, compared with those with normal BMI. The impact of potential mediators was minimal.

INTERPRETATION

Maternal obesity alone and obesity with other risk factors are associated with an increased risk of stillbirth. This risk increases with gestational age, especially at term.

Relationship Between Gestational Weight Gain and Health Service Utilization in Early Childhood: A Retrospective Cohort Study

OBJECTIVE

Gestational weight gain (GWG) outside recommended ranges can negatively impact both the woman and child. The long-term effects of below-recommended or above-recommended GWG on the child are unclear.

METHODS

This retrospective cohort study used a population-based birth registry of 258,005 live births to evaluate the relationship between maternal GWG and paediatric health service use.

RESULTS

The results suggest below recommended GWG in underweight women in particular is associated with an increased rate of hospitalizations and specialist visits for the child in the first 24 months.

CONCLUSION

Findings indicate that GWG may impact paediatric outcomes in ways that depend on pre-pregnancy body mass index, as derived from maternal height and weight measures.

Etiology of stillbirth in a tertiary care center: a retrospective cohort study assessing ultrasound, laboratory, and pathology investigations

BACKGROUND

Canadian stillbirth data are limited, and a significant proportion of pregnancies resulting in stillbirth have no attributable cause. The objective of this study was to characterize stillbirth case investigations and management at a tertiary care hospital in Ontario, Canada.

METHODS

This was a retrospective chart review study of all cases of singleton stillbirth at The Ottawa Hospital between 1 January 2012 and 31 December 2017. Terminations and multiples stillbirths were excluded. Chart reviews were conducted to extract maternal sociodemographic, obstetrical, and fetal characteristics, including results from antenatal ultrasounds, autopsy, placenta pathology, and laboratory investigations.

RESULTS

A total of 155 eligible cases of stillbirth were identified, resulting in a 6-year stillbirth rate of 4.2 per 1000 total births. The median maternal age was 31.0 years (IQR: 29.0, 35.0) and the median gestational age at delivery was 28 weeks (IQR: 24, 35). A total of 9 (5.8%) pregnant individuals had a history of previous stillbirth. Of the 155 stillbirths, 35% underwent the full suite of post-loss laboratory, placental, and fetal autopsy investigations. 63.2% of cases had post-loss laboratory investigations completed. 76% and 71% of cases had fetal autopsy and placenta pathology evaluations completed, respectively. Antenatal characteristics associated with stillbirth included fetal anomalies/genetic markers (27.1%), umbilical cord and placental anomalies (24.5%), fetal growth abnormalities (27.7%), cervical/uterine abnormalities (11.6%), and amniotic fluid abnormalities (25.1%). The most common autopsy findings included evidence of infection (22.7%), fetal anomalies (12.6%), and fetal hypoxia (10%). The most common placental pathology findings included features of placental insufficiency (21.8%), retroplacental abnormalities (16.3%), and umbilical cord accident/infarct (15.4%).

CONCLUSIONS

Our findings demonstrate that as many as two-thirds of singleton stillbirth cases at our center did not receive the post-perinatal loss investigations recommended by clinical practice guidelines. More thorough collection of post-stillbirth data at all levels (institutional, provincial, national) is warranted to improve our understanding of stillbirth epidemiology, etiology, and management in Canada.

Gestational weight loss and fetal growth in uncomplicated pregnancies among women with obesity: a population-based retrospective cohort study

OBJECTIVE

The impact of gestational weight loss (GWL) on fetal growth among women with obesity remains unclear. This study aimed to examine the association between weight loss during pregnancy among women with body mass index (BMI) ≥ 30 kg/m2 and the risk of small-for-gestational-age (SGA) and large-for-gestational-age (LGA) neonates.

METHODS

We conducted a retrospective, population-based cohort study of women with pre-pregnancy obesity that resulted in a singleton live birth in 2012-2017, using birth registry data in Ontario, Canada. Women with pregnancy complications or health conditions which could cause weight loss were excluded. GWL is defined as negative gestational weight change (≤0 kg). The association between GWL and fetal growth was estimated using generalized estimating equation models and restricted cubic spline regression analysis. Stratified analysis was conducted by obesity class (I:30-34.9 kg/m2, II:35-39.9 kg/m2, and III + : ≥40 kg/m2).

RESULTS

Of the 52,153 eligible women who entered pregnancy with a BMI ≥ 30 kg/m2, 5.3% had GWL. Compared to adequate gestational weight gain, GWL was associated with an increased risk of SGA neonates (aRR:1.45, 95% CI: 1.30-1.60) and a decreased risk of LGA neonates (aRR: 0.81, 95% CI:0.73-0.93). Non-linear L-shaped associations were observed between gestational weight change and SGA neonates, with an increased risk of SGA observed with increased GWL. On the contrary, non-linear S-shaped associations were observed between gestational weight change and LGA neonates, with a decreased risk of LGA observed with increased GWL. Similar findings were observed from the stratified analysis by obesity class.

CONCLUSION

These findings highlight that GWL in women with obesity may increase the risk of SGA neonates but reduce the risk of LGA neonates. Recommendations of GWL for women with obesity should be interpreted with caution.

Pregnancy and neonatal outcomes following malignancy in pregnancy at a tertiary care Canadian center: a retrospective chart review

Objective: Data on pregnancy-associated cancers (PACs) are lacking. The objectives of this study were to determine the incidence of PACs and describe the characteristics and outcomes of pregnancies affected by malignancy at a single tertiary care center in Ottawa, Canada.Methods: This was a retrospective chart review of individuals with PAC at The Ottawa Hospital (TOH) between 2011-2022. Eligible cases were identified from the TOH Data Warehouse, the TOH instance of the Better Outcomes Registry & Network Ontario, and the TOH Division of Maternal Fetal Medicine's Perinates database. Chart reviews were conducted to confirm case eligibility and to extract demographic, oncologic, obstetrical, and neonatal measures. The annual incidence of PAC over the 11-year period was reported per 1000 deliveries. Descriptive statistics were used to describe the sample, including frequency (n) and proportions (%) for categorical variables and mean and standard deviation (SD) for continuous variables.Results: The final cohort included 59 individuals with PAC at TOH between 2011-2022. The annual incidence of PAC ranged from 0.47 to 1.54 per 1000 deliveries. The most common PACs were breast cancer (28.8%), Hodgkin lymphoma (10.2%), and thyroid cancer (8.5%). Common interventions during pregnancy included chemotherapy (33.9%) and surgical intervention (32.2%). A total of 19 individuals (32.2%) did not undergo PAC-related treatment during pregnancy. There were 55 livebirths (91.7%), 2 spontaneous abortions (3.3%), 3 induced abortions (5.0%), and no stillbirths. Among livebirths, the mean gestational age was 37.4 ± 2.8 weeks and the mean birthweight was 2920.3 ± 650.0 g. All neonates had reassuring 5-minute Apgar scores, 18 (32.7%) were admitted to the Neonatal Intensive Care Unit/Special Care Nursery (NICU/SCN), and 8 (14.5%) were noted to have a mild congenital abnormality.Conclusion: This study shows promising perinatal outcomes for patients with PAC and their neonates. Ongoing surveillance of PAC is needed to better inform care for this patient population.

Development and evaluation of an algorithm to link mothers and infants in two US commercial healthcare claims databases for pharmacoepidemiology research

BACKGROUND

Administrative healthcare claims databases are used in drug safety research but are limited for investigating the impacts of prenatal exposures on neonatal and pediatric outcomes without mother-infant pair identification. Further, existing algorithms are not transportable across data sources. We developed a transportable mother-infant linkage algorithm and evaluated it in two, large US commercially insured populations.

METHODS

We used two US commercial health insurance claims databases during the years 2000 to 2021. Mother-infant links were constructed where persons of female sex 12-55 years of age with a pregnancy episode ending in live birth were associated with a person who was 0 years of age at database entry, who shared a common insurance plan ID, had overlapping insurance coverage time, and whose date of birth was within ± 60-days of the mother's pregnancy episode live birth date. We compared the characteristics of linked vs. non-linked mothers and infants to assess similarity.

RESULTS

The algorithm linked 3,477,960 mothers to 4,160,284 infants in the two databases. Linked mothers and linked infants comprised 73.6% of all mothers and 49.1% of all infants, respectively. 94.9% of linked infants' dates of birth were within ± 30-days of the associated mother's pregnancy episode end dates. Characteristics were largely similar in linked vs. non-linked mothers and infants. Differences included that linked mothers were older, had longer pregnancy episodes, and had greater post-pregnancy observation time than mothers with live births who were not linked. Linked infants had less observation time and greater healthcare utilization than non-linked infants.

CONCLUSIONS

We developed a mother-infant linkage algorithm and applied it to two US commercial healthcare claims databases that achieved a high linkage proportion and demonstrated that linked and non-linked mother and infant cohorts were similar. Transparent, reusable algorithms applied to large databases enable large-scale research on exposures during pregnancy and pediatric outcomes with relevance to drug safety. These features suggest studies using this algorithm can produce valid and generalizable evidence to inform clinical, policy, and regulatory decisions.

Planning and implementing practice changes in Ontario maternal-newborn hospital units: a secondary qualitative analysis

BACKGROUND

Moving evidence into practice is complex, and pregnant and birthing people and their infants do not always receive care that aligns with the best available evidence. Implementation science can inform how to effectively move evidence into practice. While there are a growing number of examples of implementation science being studied in maternal-newborn care settings, it remains unknown how real-world teams of healthcare providers and leaders approach the overall implementation process when making practice changes. The purpose of this study was to describe maternal-newborn hospital teams' approaches to implementing practice changes. We aimed to identify what implementation steps teams take (or not) and identify strengths and potential areas for improvement based on best practices in implementation science.

METHODS

We conducted a supplementary qualitative secondary analysis of 22 interviews completed in 2014-2015 with maternal-newborn nursing leaders in Ontario, Canada. We used directed content analysis to code the data to seven steps in an implementation framework (Implementation Roadmap): identify the problem and potential best practice; assemble local evidence; select and customize best practice; discover barriers and drivers; tailor implementation strategies; field-test, plan evaluation, prepare to launch; launch, evaluate, and sustain. Frequency counts are presented for each step.

RESULTS

Participants reported completing a median of 4.5 of 7 Implementation Roadmap steps (range = 3-7), with the most common being identifying a practice problem. Other steps were described less frequently (e.g., selecting and adapting evidence, field-testing, outcome evaluation) or discussed frequently but not optimally (e.g., barriers assessment). Participants provided examples of how they engaged point-of-care staff throughout the implementation process, but provided fewer examples of engaging pregnant and birthing people and their families. Some participants stated they used a formal framework or process to guide their implementation process, with the most common being quality improvement approaches and tools.

CONCLUSIONS

We identified variability across the 22 hospitals in the implementation steps taken. While we observed many strengths, we also identified areas where further support may be needed. Future work is needed to create opportunities and resources to support maternal-newborn healthcare providers and leaders to apply principles and tools from implementation science to their practice change initiatives.

The Minimum Data Set for Rare Diseases: Systematic Review

BACKGROUND

The minimum data set (MDS) is a collection of data elements to be grouped using a standard approach to allow the use of data for clinical and research purposes. Health data are typically voluminous, complex, and sometimes too ambiguous to generate indicators that can provide knowledge and information on health. This complexity extends further to the rare disease (RD) domain. MDSs are essential for health surveillance as they help provide services and generate recommended population indicators. There is a bottleneck in international literature that reveals a global problem with data collection, recording, and structuring in RD.

OBJECTIVE

This study aimed to identify and analyze the MDSs used for RD in health care networks worldwide and compare them with World Health Organization (WHO) guidelines.

METHODS

The population, concept, and context methodology proposed by the Joanna Briggs Institute was used to define the research question of this systematic review. A total of 4 databases were reviewed, and all the processes were reported using the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) methodology. The data elements were analyzed, extracted, and organized into 10 categories according to WHO digital health guidelines. The quality assessment used the STROBE (Strengthening the Reporting of Observational Studies in Epidemiology) checklist.

RESULTS

We included 20 studies in our review, 70% (n=14) of which focused on a specific health domain and 30% (n=6) of which referred to RD in general. WHO recommends that health systems and networks use standard terminology to exchange data, information, knowledge, and intelligence in health. However, there was a lack of terminological standardization of the concepts in MDSs. Moreover, the selected studies did not follow the same standard structure for classifying the data from their MDSs. All studies presented MDSs with limitations or restrictions because they covered only a specific RD, or their scope of application was restricted to a specific context or geographic region. Data science methods and clinical experience were used to design, structure, and recommend a fundamental global MDS for RD patient records in health care networks.

CONCLUSIONS

Our study highlights the difficulties in standardizing and categorizing findings from MDSs for RD because of the varying structures used in different studies. The fundamental RD MDS designed in this study comprehensively covers the data needs in the clinical and management sectors. These results can help public policy makers support other aspects of their policies. We highlight the potential of our results to help strategic decisions related to RD.

TRIAL REGISTRATION

PROSPERO CRD42021221593; https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=221593.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

RR2-10.1016/j.procs.2021.12.034.

Pregnancy, fetal, and neonatal outcomes after a first booster dose of covid-19 vaccine during pregnancy in Ontario, Canada: population based, retrospective cohort study

Objective

To assess risk of adverse pregnancy, fetal, and neonatal outcomes after a third dose (first booster dose) of covid-19 vaccine during pregnancy among individuals who had completed both doses of primary covid-19 vaccine series before pregnancy.

Design

Population based, retrospective cohort study.

Setting

Ontario, Canada, from 20 December 2021 to 31 August 2022.

Participants

Individuals were included if they were pregnant with an expected date of delivery from 20 December 2021 (start date of third dose eligibility for everyone ≥18 years) to 31 August 2022, who had completed the two doses of primary covid-19 messenger RNA vaccine series before pregnancy, and became eligible for a third dose (≥six months since dose two) before the end of pregnancy.

Main outcome measures

Pregnancy outcomes included hypertensive disorders of pregnancy, placental abruption, caesarean delivery, chorioamnionitis, and postpartum hemorrhage. Fetal and neonatal outcomes included stillbirth, preterm birth, admission to neonatal intensive care unit for >24 h, newborn 5 min Apgar score <7, and small-for-gestational age infant (<10th percentile). We estimated hazard ratios and 95% confidence intervals for study outcomes, treating dose three as a time varying exposure and adjusting for confounding using inverse probability weighting.

Results

Among 32 689 births, 18 491 (56.6%) were born to individuals who received a third covid-19 dose during pregnancy. Compared with eligible individuals who did not receive a third dose during pregnancy, no increased risks were associated with receiving a third covid-19 vaccine dose during pregnancy for placental abruption (adjusted hazard ratio 0.84 (95% confidence interval 0.70 to 1.02)), chorioamnionitis (0.67 (0.49 to 0.90)), postpartum haemorrhage (1.01 (0.89 to 1.16)), caesarean delivery (0.90 (0.87 to 0.94)), stillbirth (0.56 (0.39 to 0.81)), preterm birth (0.91 (0.84 to 0.99)), neonatal intensive care unit admission (0.96 (0.90 to 1.03)), 5 min Apgar score<7 (0.96 (0.82 to 1.14)), or small-for-gestational age infant (0.86 (0.79 to 0.93)).

Conclusion

Receipt of a third covid-19 vaccine dose during pregnancy was not associated with an increased risk of adverse pregnancy, fetal, or neonatal outcomes. These findings can help to inform evidence based decision making about the risks and benefits of covid-19 booster doses during pregnancy.

Critical windows of exposure to air pollution and gestational diabetes: assessing effect modification by maternal pre-existing conditions and environmental factors

BACKGROUND

Ambient air pollution has been associated with gestational diabetes (GD), but critical windows of exposure and whether maternal pre-existing conditions and other environmental factors modify the associations remains inconclusive.

METHODS

We conducted a retrospective cohort study of all singleton live birth that occurred between April 1^st 2006 and March 31^st 2018 in Ontario, Canada. Ambient air pollution data (i.e., fine particulate matter with a diameter ≤ 2.5 μm (PM_2.5), nitrogen dioxide (NO₂) and ozone (O₃)) were assigned to the study population in spatial resolution of approximately 1 km × 1 km. The Normalized Difference Vegetation Index (NDVI) and the Green View Index (GVI) were also used to characterize residential exposure to green space as well as the Active Living Environments (ALE) index to represent the active living friendliness. Multivariable Cox proportional hazards regression models were used to evaluate the associations.

RESULTS

Among 1,310,807 pregnant individuals, 68,860 incident cases of GD were identified. We found the strongest associations between PM_2.5 and GD in gestational weeks 7 to 18 (HR = 1.07 per IQR (2.7 µg/m³); 95% CI: 1.02 - 1.11)). For O₃, we found two sensitive windows of exposure, with increased risk in the preconception period (HR = 1.03 per IQR increase (7.0 ppb) (95% CI: 1.01 - 1.06)) as well as gestational weeks 9 to 28 (HR 1.08 per IQR (95% CI: 1.04 -1.12)). We found that women with asthma were more at risk of GD when exposed to increasing levels of O₃ (p- value for effect modification = 0.04). Exposure to air pollutants explained 20.1%, 1.4% and 4.6% of the associations between GVI, NDVI and ALE, respectively.

CONCLUSION

An increase of PM_2.5 exposure in early pregnancy and of O₃ exposure during late first trimester and over the second trimester of pregnancy were associated with gestational diabetes whereas exposure to green space may confer a protective effect.

Risk of interpersonal violence during and after pregnancy among people with schizophrenia: a population-based cohort study

BACKGROUND

Schizophrenia is associated with increased risk of experiencing interpersonal violence. Little is known about risk specifically around the time of pregnancy.

METHODS

This population-based cohort study included all individuals (aged 15-49 yr) listed as female on their health cards who had a singleton birth in Ontario, Canada, between 2004 and 2018. We compared those with and without schizophrenia on their risk of an emergency department (ED) visit for interpersonal violence in pregnancy or within 1 year postpartum. We adjusted relative risks (RRs) for demographics, prepregnancy history of substance use disorder and history of interpersonal violence. In a subcohort analysis, we used linked clinical registry data to evaluate interpersonal violence screening and self-reported interpersonal violence during pregnancy.

RESULTS

We included 1 802 645 pregnant people, 4470 of whom had a diagnosis of schizophrenia. Overall, 137 (3.1%) of those with schizophrenia had a perinatal ED visit for interpersonal violence, compared with 7598 (0.4%) of those without schizophrenia, for an RR of 6.88 (95% confidence interval [CI] 5.66-8.37) and an adjusted RR of 3.44 (95% CI 2.86-4.15). Results were similar when calculated separately for the pregnancy (adjusted RR 3.47, 95% CI 2.68-4.51) period and the first year postpartum (adjusted RR 3.45, 95% CI 2.75-4.33). Pregnant people with schizophrenia were equally likely to be screened for interpersonal violence (74.3% v. 73.8%; adjusted RR 0.99, 95% CI 0.95-1.04), but more likely to self-report it (10.2% v. 2.4%; adjusted RR 3.38, 95% CI 2.61-4.38), compared with those without schizophrenia. Among patients who did not self-report interpersonal violence, schizophrenia was associated with an increased risk for a perinatal ED visit for interpersonal violence (4.0% v. 0.4%; adjusted RR 6.28, 95% CI 3.94-10.00).

INTERPRETATION

Pregnancy and postpartum are periods of higher risk for interpersonal violence among people with schizophrenia compared with those without schizophrenia. Pregnancy is a key period for implementing violence prevention strategies in this population.

Temporal trends and determinants of COVID-19 vaccine coverage and series initiation during pregnancy in Ontario, Canada, December 2020 to December 2021: A population-based retrospective cohort study

BACKGROUND

Population-based COVID-19 vaccine coverage estimates among pregnant individuals are limited. We assessed temporal patterns in vaccine coverage (≥1 dose before or during pregnancy) and evaluated factors associated with vaccine series initiation (receiving dose 1 during pregnancy) in Ontario, Canada.

METHODS

We linked the provincial birth registry with COVID-19 vaccination records from December 14, 2020 to December 31, 2021 and assessed coverage rates among all pregnant individuals by month, age, and neighborhood sociodemographic characteristics. Among individuals who gave birth since April 2021-when pregnant people were prioritized for vaccination-we assessed associations between sociodemographic, behavioral, and pregnancy-related factors with vaccine series initiation using multivariable regression to estimate adjusted risk ratios (aRR) and risk differences (aRD) with 95% confidence intervals (CI).

RESULTS

Among 221,190 pregnant individuals, vaccine coverage increased to 71.2% by December 2021. Gaps in coverage across categories of age and sociodemographic characteristics decreased over time, but did not disappear. Lower vaccine series initiation was associated with lower age (<25 vs. 30-34 years: aRR 0.53, 95%CI 0.51-0.56), smoking (vs. non-smoking: 0.64, 0.61-0.67), no first trimester prenatal care visit (vs. visit: 0.80, 0.77-0.84), and residing in neighborhoods with the lowest income (vs. highest: 0.69, 0.67-0.71). Vaccine series initiation was marginally higher among individuals with pre-existing medical conditions (vs. no conditions: 1.07, 1.04-1.10).

CONCLUSIONS

COVID-19 vaccine coverage among pregnant individuals remained lower than in the general population, and there was lower vaccine initiation by multiple characteristics.

Perinatal and pediatric outcomes associated with the use of fertility treatment: a population-based retrospective cohort study in Ontario, Canada

BACKGROUND

Around 2% of births in Ontario, Canada involve the use of assisted reproductive technology (ART), and it is rising due to the implementation of a publicly funded ART program in 2016. To better understand the impact of fertility treatments, we assessed perinatal and pediatric health outcomes associated with ART, hormonal treatments, and artificial insemination compared with spontaneously conceived births.

METHODS

This population-based retrospective cohort study was conducted using provincial birth registry data linked with fertility registry and health administrative databases in Ontario, Canada. Live births and stillbirths from January 2013 to July 2016 were included and followed to age one. The risks of adverse pregnancy, birth and infant health outcomes were assessed by conception method (spontaneous conception, ART - in vitro fertilization and non-ART - ovulation induction, intra-uterine or vaginal insemination) using risk ratios and incidence rate ratios with 95% confidence intervals (CI). Propensity score weighting using a generalized boosted model was applied to adjust for confounding.

RESULT(S)

Of 177,901 births with a median gestation age of 39 weeks (IQR 38.0-40.0), 3,457 (1.9%) were conceived via ART, and 3,511 (2.0%) via non-ART treatments. There were increased risks (adjusted risk ratio [95% CI]) of cesarean delivery (ART: 1.44 [1.42-1.47]; non-ART: 1.09 [1.07-1.11]), preterm birth (ART: 2.06 [1.98-2.14]; non-ART: 1.85 [1.79-1.91]), very preterm birth (ART: 2.99 [2.75-3.25]; non-ART: 1.89 [1.67-2.13]), 5-min Apgar < 7 (ART: 1.28 [1.16-1.42]; non-ART: 1.62 [1.45-1.81]), and composite neonatal adverse outcome indicator (ART: 1.61 [1.55-1.68]; non-ART: 1.29 [1.25-1.34]). Infants born after fertility treatments had increased risk of admission to neonatal intensive care unit (ART: 1.98 [1.84-2.13]; non-ART: 1.59 [1.51-1.67]) and prolonged birth admission (≥ 3 days) (ART: 1.60 [1.54-1.65]; non-ART: 1.42 [1.39-1.45]). The rate of emergency and in-hospital health services use within the first year was significantly increased for both exposure groups and remained elevated when limiting analyses to term singletons.

CONCLUSION(S)

Fertility treatments were associated with increased risks of adverse outcomes; however, the overall magnitude of risks was lower for infants conceived via non-ART treatments.

Fresh Compared With Frozen Embryo Transfer and Risk of Severe Maternal Morbidity: A Study of In Vitro Fertilization Pregnancies in Ontario, Canada

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.

Cytogenetic outcomes following a failed cell-free DNA screen: a population-based retrospective cohort study of 35,146 singleton pregnancies

BACKGROUND

Cell-free fetal DNA screening is routinely offered to pregnant individuals to screen for aneuploidies. Although cell-free DNA screening is consistently more accurate than multiple-marker screening, it sometimes fails to yield a result. These test failures and their clinical implications are poorly described in the literature. Some studies suggest that a failed cell-free DNA screening result is associated with increased likelihood of cytogenetic abnormalities.

OBJECTIVE

This study aimed to assess the association between a failed cell-free DNA test and common aneuploidies. The objectives were to determine: (1) the proportion of test failures on first and subsequent attempts, and (2) whether a failed cell-free DNA screen on first attempt is associated with increased likelihood of common aneuploidies (trisomies 21, 18, and 13, and sex chromosome aneuploidies).

STUDY DESIGN

This was a population-based retrospective cohort study using data from Ontario's prescribed maternal and child registry, Better Outcomes Registry and Network Ontario. The study included all singleton pregnancies in Ontario with an estimated date of delivery from September 1, 2016 to March 31, 2019 that had a cell-free DNA screening record in the registry. Specific outcomes (trisomies 21, 18, and 13, and sex chromosome aneuploidies) of pregnancies with a failed cell-free DNA screen on first attempt were compared with those of pregnancies with low-risk cell-free DNA-screening results using modified Poisson regression adjusted for funding status (publicly funded vs self-paid), gestational age at screening, method of conception, and maternal age for autosomal aneuploidies.

RESULTS

Our cohort included 35,146 pregnancies that had cell-free DNA screening during the study period. The overall cell-free DNA screening failure rate was 4.8% on first attempt and 2.2% after multiple attempts. An abnormal cytogenetic result for trisomies 21, 18, and 13, or sex chromosome aneuploidies was identified in 19.4% of pregnancies with a failed cell-free DNA screening for which cytogenetic testing was performed. Pregnancies with a failed cell-free DNA screen on first attempt had a relative risk of 130.3 (95% confidence interval, 64.7-262.6) for trisomy 21, trisomy 18, or trisomy 13, and a risk difference of 5.4% (95% confidence interval, 2.6-8.3), compared with pregnancies with a low-risk result. The risk of sex chromosome aneuploidies was not significantly greater in pregnancies with a failed result compared with pregnancies with a low-risk result (relative risk, 2.7; 95% confidence interval, 0.9-7.9; relative difference, 1.2%; 95% confidence interval, -0.9 to 3.2).

CONCLUSION

Cell-free DNA screening test failures are relatively common. Although repeated testing improves the likelihood of an informative result, pregnancies with a failed cell-free DNA screen upon first attempt remain at increased risk for common autosomal aneuploidies, but not sex chromosome aneuploidies.

The use, perceptions and knowledge of safety of over-the-counter medications during pregnancy in a Canadian population

BACKGROUND

The prevalence of prenatal over-the-counter medication use in Canadian women is unknown.

METHODS

A cross-sectional study of prenatal over-the-counter medication use and safety knowledge was conducted among pregnant and post-partum women attending an academic hospital obstetrics clinic.

RESULTS

Seventy-two women participated; 90.3% were Caucasian, 69.4% had a college/university degree, and 61.1% lived in an urban area. Of the 72 women, 87.5% used over-the-counter medications prenatally, first (55.6%), second (65.3%), and third (47.2%) trimesters, with prenatal acetaminophen use most common (72.2%). Women who used over-the-counter medications 1-0onths before conception were more likely to use over-the-counter medications during pregnancy, and 18% of women initiated over-the-counter medications in pregnancy. Women self-reported a medium level of over-the-counter medication safety knowledge (73.6%) and responded that not all over-the-counter medications are safe during pregnancy (95.8%).

CONCLUSION

Despite limited safety profiles of some over-the-counter medications, pre-conception and prenatal over-the-counter medication use was high. Further research on the risk of over-the-counter medications and combinations in pregnancy is needed to help women to make safe choices during pregnancy.

Risk of preterm birth, small for gestational age at birth, and stillbirth after covid-19 vaccination during pregnancy: population based retrospective cohort study

OBJECTIVE

To assess the risk of preterm birth, small for gestational age at birth, and stillbirth after covid-19 vaccination during pregnancy.

DESIGN

Population based retrospective cohort study.

SETTING

Ontario, Canada, 1 May to 31 December 2021.

PARTICIPANTS

All liveborn and stillborn infants from pregnancies conceived at least 42 weeks before the end of the study period and with gestational age ≥20 weeks or birth weight ≥500 g.

MAIN OUTCOME MEASURES

Using Cox regression, hazard ratios and 95% confidence intervals were estimated for preterm birth before 37 weeks (overall and spontaneous preterm birth), very preterm birth (<32 weeks), small for gestational age at birth (<10th centile), and stillbirth. Vaccination against covid-19 was treated as a time varying exposure in the outcome specific risk window, and propensity score weighting was used to adjust hazard ratios for potential confounding.

RESULTS

Among 85 162 births, 43 099 (50.6%) occurred in individuals who received one dose or more of a covid-19 vaccine during pregnancy-42 979 (99.7%) received an mRNA vaccine. Vaccination during pregnancy was not associated with any increased risk of overall preterm birth (6.5% among vaccinated v 6.9% among unvaccinated; adjusted hazard ratio 1.02, 95% confidence interval 0.96 to 1.08), spontaneous preterm birth (3.7% v 4.4%; 0.96, 0.90 to 1.03), or very preterm birth (0.59% v 0.89%; 0.80, 0.67 to 0.95). No increase was found in risk of small for gestational age at birth (9.1% v 9.2%; 0.98, 0.93 to 1.03) or stillbirth (0.25% v 0.44%; 0.65, 0.51 to 0.84). Findings were similar by trimester of vaccination, mRNA vaccine product, and number of doses received during pregnancy.

CONCLUSION

The findings suggest that vaccination against covid-19 during pregnancy is not associated with a higher risk of preterm birth, small for gestational age at birth, or stillbirth.

Prevalence of SARS-CoV-2 infection among obstetric patients in Ottawa, Canada: a descriptive study

BACKGROUND

There is limited information on the prevalence of SARS-CoV-2 infection in obstetric settings in Canada, beyond the first wave of the COVID-19 pandemic (February to June 2020). We sought to describe the prevalence of SARS-CoV-2 infection in pregnant people admitted to triage units at a tertiary care hospital in Ottawa, Canada.

METHODS

We conducted a descriptive study of pregnant people admitted to obstetric triage assessment units at The Ottawa Hospital between Oct. 19 and Nov. 27, 2020 (second local wave of the COVID-19 pandemic). Participants underwent SARS-CoV-2 polymerase chain reaction (PCR) (via naso- or oropharyngeal swabs) and serology testing upon admission. We excluded individuals younger than 18 years, those who did not speak English or French, those who enrolled in conflicting studies, those admitted for pregnancy termination and those triaged between 11:31 pm and 7:29 am. Swab and serology samples were analyzed using digital droplet PCR and enzyme-linked immunosorbent assays, respectively. We defined SARS-CoV-2 seropositivity as a positive result for immunoglobulin (Ig) G, either alone or in combination with IgM or IgA.

RESULTS

Of the 632 eligible patients, 363 (57.4%) consented to participation and 362 collectively provided 284 swab and 352 blood samples eligible for analysis. Common reasons for declining participation included feeling overwhelmed or anxious, being worried about repercussions of testing, pain or discomfort with testing or disinterest in research. Participants were mostly multiparous (53.9%) and in their third trimester upon admission (88.4%). In all, 18 (4.9%) participants had evidence of SARS-CoV-2 exposure; 2 (0.7%) of 284 were positive for SARS-CoV-2 by PCR and 16 (4.5%) of 352 were positive for IgG antibodies to SARS-CoV-2.

INTERPRETATION

During the second local wave of the COVID-19 pandemic, the prevalence of active SARS-CoV-2 infection among obstetric patients in Ottawa was 0.7% and seroprevalence was 4.5%. Our low participation rate highlights the need for improvements in patient education and public health messaging on the benefits of SARS-CoV-2 testing programs.

Exposure to Intrapartum Epidural Analgesia and Risk of Autism Spectrum Disorder in Offspring

IMPORTANCE

There is conflicting evidence on the association between intrapartum epidural analgesia and risk of autism spectrum disorder (ASD) in offspring.

OBJECTIVE

To evaluate the association between intrapartum epidural analgesia and the risk of ASD in offspring.

DESIGN, SETTING, AND PARTICIPANTS

This population-based cohort study was conducted in Ontario, Canada, using the health and administrative records of singleton live births by vaginal delivery between April 1, 2006, and March 31, 2014. Neonates with less than 24 weeks' gestation or weighing less than 500 g were excluded. Offspring were followed up from 18 months of age until ASD diagnosis, loss to follow-up, or the end of the study (December 31, 2020), whichever occurred first. Exposure, covariate, and outcome data were obtained using provincial health administrative databases.

EXPOSURES

Any intrapartum exposure to epidural or combined spinal-epidural analgesia.

MAIN OUTCOMES AND MEASURES

The primary outcome was ASD diagnosis after 18 months of age. Inverse probability of treatment weighting (IPTW) of Cox proportional hazards regression models was used to estimate the hazard ratio (HR) of intrapartum epidural analgesia and ASD in offspring. Offspring head injury was used as a control outcome. Models were adjusted for maternal sociodemographic factors, health behaviors, and medical and obstetrical history as well as labor, delivery, and offspring characteristics. Post hoc analyses included restriction to term neonates, a conditional within-mother analysis, exclusion of records with concomitant intrapartum pain management exposures, a complete case analysis, use of an alternative ASD definition, and estimation of the average treatment effect in the treated group.

RESULTS

Among the 650 373 mother-offspring pairs included in the study, 418 761 (64.4%) were exposed to intrapartum epidural analgesia. The mean (SD) maternal age at delivery was 29.7 (5.5) years; the offspring had a mean (SD) gestational age at delivery of 39.1 (1.6) weeks and included 329 808 male newborns (50.7%). The exposed and unexposed groups were similar in all maternal and newborn characteristics after IPTW (standardized difference <0.10). Autism spectrum disorder was diagnosed in 7546 offspring (1.8%) of mothers who received intrapartum epidural analgesia (incidence rate, 18.8 [95% CI, 18.4-19.3] per 10 000 person-years) compared with 3234 offspring (1.4%) who were unexposed (incidence rate, 14.4 [95% CI, 13.9-14.9] per 10 000 person-years). The crude HR for ASD associated with intrapartum epidural analgesia was 1.30 (95% CI, 1.25-1.36), and the IPTW-adjusted HR was 1.14 (95% CI, 1.08-1.21). Results did not qualitatively differ in post hoc analyses.

CONCLUSIONS AND RELEVANCE

Results of this study showed that intrapartum epidural analgesia was associated with a small increase in risk for ASD in offspring. The biological plausibility of this association, however, remains unclear, and the finding must be interpreted with caution.

Association of COVID-19 Vaccination in Pregnancy With Adverse Peripartum Outcomes

Importance

There is limited comparative epidemiological evidence on outcomes associated with COVID-19 vaccination during pregnancy; monitoring pregnancy outcomes in large populations is required.

Objective

To evaluate peripartum outcomes following COVID-19 vaccination during pregnancy.

Design, Setting, and Participants

Population-based retrospective cohort study in Ontario, Canada, using a birth registry linked with the provincial COVID-19 immunization database. All births between December 14, 2020, and September 30, 2021, were included.

Exposures

COVID-19 vaccination during pregnancy, COVID-19 vaccination after pregnancy, and no vaccination.

Main Outcomes and Measures

Postpartum hemorrhage, chorioamnionitis, cesarean delivery (overall and emergency cesarean delivery), admission to neonatal intensive care unit (NICU), and low newborn 5-minute Apgar score (<7). Linear and robust Poisson regression was used to generate adjusted risk differences (aRDs) and risk ratios (aRRs), respectively, comparing cumulative incidence of outcomes in those who received COVID-19 vaccination during pregnancy with those vaccinated after pregnancy and those with no record of COVID-19 vaccination at any point. Inverse probability of treatment weights were used to adjust for confounding.

Results

Among 97 590 individuals (mean [SD] age, 31.9 [4.9] years), 22 660 (23%) received at least 1 dose of COVID-19 vaccine during pregnancy (63.6% received dose 1 in the third trimester; 99.8% received an mRNA vaccine). Comparing those vaccinated during vs after pregnancy (n = 44 815), there were no significantly increased risks of postpartum hemorrhage (incidence: 3.0% vs 3.0%; aRD, -0.28 per 100 individuals [95% CI, -0.59 to 0.03]; aRR, 0.91 [95% CI, 0.82-1.02]), chorioamnionitis (0.5% vs 0.5%; aRD, -0.04 per 100 individuals [95% CI, -0.17 to 0.09]; aRR, 0.92 [95% CI, 0.70-1.21]), cesarean delivery (30.8% vs 32.2%; aRD, -2.73 per 100 individuals [95% CI, -3.59 to -1.88]; aRR, 0.92 [95% CI, 0.89-0.95]), NICU admission (11.0% vs 13.3%; aRD, -1.89 per 100 newborns [95% CI, -2.49 to -1.30]; aRR, 0.85 [95% CI, 0.80-0.90]), or low Apgar score (1.8% vs 2.0%; aRD, -0.31 per 100 newborns [95% CI, -0.56 to -0.06]; aRR, 0.84 [95% CI, 0.73-0.97]). Findings were qualitatively similar when compared with individuals who did not receive COVID-19 vaccination at any point (n = 30 115).

Conclusions and Relevance

In this population-based cohort study in Ontario, Canada, COVID-19 vaccination during pregnancy, compared with vaccination after pregnancy and with no vaccination, was not significantly associated with increased risk of adverse peripartum outcomes. Study interpretation should consider that the vaccinations received during pregnancy were primarily mRNA vaccines administered in the second and third trimester.

Maternal-Newborn Health System Changes and Outcomes in Ontario Canada during Wave 1 of the COVID-19 Pandemic - A Retrospective Study

OBJECTIVE

To determine the population-level impact of COVID-19 pandemic-related obstetric practice changes on maternal and newborn outcomes.

METHODS

Segmented regression analysis examined changes that occurred 240 weeks pre-pandemic through the first 32 weeks of the pandemic using data from Ontario's Better Outcomes Registry & Network. Outcomes included birth location, length of stay, labour analgesia, mode of delivery, preterm birth, and stillbirth. Immediate and gradual effects were modelled with terms representing changes in intercepts and slopes, corresponding to the start of the pandemic.

RESULTS

There were 799 893 eligible pregnant individuals included in the analysis; 705 767 delivered in the pre-pandemic period and 94,126 during the pandemic wave 1 period. Significant immediate decreases were observed for hospital births (relative risk [RR] 0.99; 95% CI 0.98-0.99), length of stay (median change -3.29 h; 95% CI -3.81 to -2.77), use of nitrous oxide (RR 0.11; 95% CI 0.09-0.13) and general anesthesia (RR 0.69; 95% CI 0.58- 0.81), and trial of labour after cesarean (RR 0.89; 95% CI 0.83-0.96). Conversely, there were significant immediate increases in home births (RR 1.35; 95% CI 1.21-1.51), and use of epidural (RR 1.02; 95% CI 1.01-1.04) and regional anesthesia (RR 1.01; 95% CI 1.01-1.02). There were no significant immediate changes for any other outcomes, including preterm birth (RR 0.99; 95% CI 0.93-1.05) and stillbirth (RR 1.11; 95% CI 0.87-1.42).

CONCLUSION

Provincial health system changes implemented at the start of the pandemic resulted in immediate clinical practice changes but no significant increases in adverse outcomes.

Performance of a universal prenatal screening program incorporating cell-free fetal DNA analysis in Ontario, Canada

BACKGROUND:

The emergence of cell-free fetal DNA (cfDNA) testing technology has disrupted the landscape of prenatal screening for trisomies 21 (T21) and 18 (T18). Publicly funded systems around the world are grappling with how to best integrate this more accurate but costly technology, as there is limited evidence about its incremental value in real-world conditions. The objectives of this study were to describe the population-based performance of Ontario’s prenatal screening program, which incorporates publicly funded cfDNA screening for specific indications, and the effect of cfDNA testing on the screening and diagnostic choices made by pregnant people.

METHODS:

We conducted a retrospective, descriptive cohort study using routinely collected data from Better Outcomes & Registry Network (BORN) Ontario, which captures linked population data for prenatal and neonatal health encounters across Ontario. We included all singleton pregnancies with an estimated due date between Sept. 1, 2016, and Mar. 31, 2019, that underwent publicly funded prenatal screening in Ontario, and a comparison cohort from Apr. 1, 2012, and Mar. 31, 2013. We assessed performance of the screening program for the detection of T21 or T18 by calculating sensitivity, specificity, positive predictive value and negative predictive value against diagnostic cytogenetic results or birth outcomes. We assessed the impact of the program by calculating the proportion of T21 screen-positive pregnancies undergoing subsequent cfDNA screening and invasive prenatal diagnostic testing.

RESULTS:

The study cohort included 373 682 pregnancies. The prenatal screening program had an uptake of 69.9%, a screen-positive rate and sensitivity of 1.6% and 89.9% for T21, and 0.2% and 80.5% for T18, respectively. The test failure rate for cfDNA screening was 2.2%. Invasive prenatal diagnostic testing decreased from 4.4% in 2012–2013 to 2.4% over the study period; 65.2% of pregnant people who received a screen-positive result from cfDNA testing went on to have invasive prenatal diagnostic testing.

INTERPRETATION:

This publicly funded screening program, incorporating cfDNA analysis for common aneuploidies, showed robust performance, a substantial reduction in invasive prenatal diagnostic testing and that pregnant people exercise autonomy in their choices about prenatal screening and diagnosis.