ArticleBMJ (Clinical research ed.)2022
Risk of preterm birth, small for gestational age at birth, and stillbirth after covid-19 vaccination during pregnancy: population based retrospective cohort study.
Article in BMJ (Clinical research ed.), 2022. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 39 papers, 2 of them syntheses that pooled it.
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The trial behind it
Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.
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Who cites it
39 citing papers in PubMed, 2 syntheses or guidelines pooled it, 74 citations in OpenAlex.
- Safety and Effectiveness of COVID-19 Vaccines During Pregnancy: A Living Systematic Review and Meta-analysis.Drug safety · 2024Pooled it
- Effectiveness and safety of COVID-19 vaccines on maternal and perinatal outcomes: a systematic review and meta-analysis.BMJ global health · 2024Pooled it
- Neonatal and Infant Health Outcomes Following Maternal COVID-19 Vaccination: CDC's COVID-19 Vaccine Pregnancy Registry.Journal of pediatric health care : official publication of National Association of Pediatric Nurse Associates & Practitioners · 2026Article
- Safety profile following mRNA-1273 COVID-19 primary vaccination in healthy adults in Indonesia.Global epidemiology · 2026Article
- SARS-CoV-2 Vaccination Before and During Pregnancy and Prevention of Infant COVID-19 Infection.Pediatrics · 2026Article
- Background incidence rates and observed-to-expected ratios of adverse events of special interest after covid-19 mRNA vaccination during pregnancy in France: a nationwide population-based study.The Lancet regional health. Europe · 2026Article
- Article
- COVID-19 vaccination around the time of conception and risk of placenta-mediated adverse pregnancy outcomes.Acta obstetricia et gynecologica Scandinavica · 2025Article
- First-Trimester mRNA COVID-19 Vaccination and Risk of Major Congenital Anomalies.JAMA network open · 2025Article
- Maternal Exposures to COVID-19 Vaccine and Adverse Birth Outcomes: National Population Study in Korea.Journal of Korean medical science · 2025Article
- The association between coronavirus disease 2019 vaccination during pregnancy and neonatal health outcomes.Pediatric investigation · 2025Article
- How do pandemic changed obstetric and neonatal outcomes: experience from a tertiary care center.Revista da Associacao Medica Brasileira (1992) · 2025Article
- The Effectiveness and Influence of COVID-19 Vaccination on Perinatal Individuals and Their Newborns: An Updated Meta-Analysis.The Canadian journal of infectious diseases & medical microbiology = Journal canadien des maladies infectieuses et de la microbiologie medicale · 2025Review
- Perceptions of influenza and SARS-CoV-2 vaccination among health care personnel in Thailand, 2024.PloS one · 2025Article
- Assessment of Placental Antioxidant Defense Markers in Vaccinated and Unvaccinated COVID-19 Third-Trimester Pregnancies.Life (Basel, Switzerland) · 2024Article
- Safety of COVID-19 Vaccination in Pregnancy: A Systematic Review.Diagnostics (Basel, Switzerland) · 2024Review
- [Pregnant women with COVID-19 ARDS on the intensive care unit].Die Anaesthesiologie · 2024Article
- Defining and reporting adverse events of special interest in comparative maternal vaccine studies: a systematic review.Vaccine: X · 2024Review
- Article
- Medication Use Among Pregnant Women With SARS-CoV-2 Infection and Risk of Hospitalization-A Study in Two Brazilian Hospitals.Journal of pregnancy · 2024Article
Corrections and comments
PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.
Authors and funding
22 authors at 9 institutions in 4 countries.
Funding
No grant is acknowledged in the PubMed record.
Abstract
objectiveTo assess the risk of preterm birth, small for gestational age at birth, and stillbirth after covid-19 vaccination during pregnancy.
designPopulation based retrospective cohort study.
settingOntario, Canada, 1 May to 31 December 2021.
participantsAll 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 measuresUsing 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.
resultsAmong 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
conclusionThe 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.
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