ArticleBMJ open2025
Safety of COVID-19 vaccines among pregnant individuals in Quebec, Canada: a population-based retrospective cohort study from the Canadian Immunization Research Network.
Article in BMJ open, 2025. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 2 papers.
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The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.
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Who cites it
2 citing papers in PubMed.
- Coadministered Influenza- and Pertussis-Containing Vaccines in Pregnant Women.JAMA network open · 2026Article
- 'Will They Have It Too?' Mothers' Perspectives of Familial Risk for Eating Disorders.Child psychiatry and human development · 2025Article
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Authors and funding
11 authors.
Funding
No grant is acknowledged in the PubMed record.
Abstract
objectiveTo estimate the association between maternal COVID-19 vaccination during pregnancy and adverse neonatal and maternal outcomes.
designPopulation-based retrospective cohort study using a hospitalisation database linked with other health administrative databases.
settingProvince of Quebec, Canada, from 1 May 2021 to 30 June 2023.
participantsAll singleton pregnancies resulting in a live birth or stillbirth at ≥20 weeks of gestation, excluding those with a conception date <42 weeks before the end of the study period. PRIMARY OUTCOME MEASURES: We used robust Poisson regression models to estimate adjusted risk ratios (aRRs) for chorioamnionitis, postpartum haemorrhage, caesarean delivery, preterm birth, very preterm birth, small for gestational age (SGA), maternal and neonatal admission to intensive care unit (ICU, NICU) and severe neonatal morbidity. We used a Cox regression model with a time-varying exposure variable to estimate adjusted HRs (aHRs) for stillbirth. Propensity score weighting was used to adjust for potential confounding.
resultsAmong 140 073 singleton pregnancies resulting in live birth or stillbirth, 61 282 individuals (43.8%) received at least one dose of messenger RNA COVID-19 vaccine during pregnancy. Vaccination during pregnancy was not associated with an increased risk of chorioamnionitis (aRR 0.99, 95% CI 0.95 to 1.04), postpartum haemorrhage (aRR 1.03, 95% CI 0.99 to 1.06), very preterm birth (aRR 1.04, 95% CI 0.89 to 1.21) and stillbirth (aHR 1.14, 95% CI 0.94 to 1.39). Vaccination during pregnancy was significantly associated with a reduced risk of caesarean delivery (aRR 0.94, 95% CI 0.92 to 0.96), maternal ICU admission (aRR 0.80, 95% CI 0.65 to 0.98), SGA (aRR 0.94, 95% CI 0.91 to 0.98), NICU admission (aRR 0.91, 95% CI 0.85 to 0.96), preterm birth (aRR 0.94, 95% CI 0.90 to 0.99) and severe neonatal morbidity (aRR 0.91, 95% CI 0.85 to 0.98).
conclusionsOur findings suggest that COVID-19 vaccination during pregnancy was not associated with an increased risk of adverse outcomes. Ongoing surveillance of the safety of maternal COVID-19 vaccination is essential as doses continue to be recommended for this group.
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