Peripartum Outcomes Associated With COVID-19 Vaccination during Pregnancy: A Systematic Review and Meta-analysis

ABSTRACT

Background. The risk and benefits of coronavirus disease 2019 (COVID-19) vaccination during pregnancy are under investigation. Pooled evidence regarding neonatal and maternal outcomes in relation to COVID-19 vaccination during pregnancy is scarce. Methods. We searched PubMed and EMBASE databases in April 2022 without language restrictions. We included Prospective trials and observational studies comparing the women who received at least one COVID-19 vaccination during pregnancy with those who did not and reporting neonatal outcomes. Two independent investigators extracted relevant data from each study. Odds ratios (ORs) were calculated using random-effects models. This study followed the Preferred Reporting Items for Systematic Reviews and Meta-analysis guidelines. The primary outcomes were the neonatal outcomes, including preterm birth, small-for-gestational-age (SGA), low Apgar score (< 7 at 5 min), neonatal intensive care units (NICU) admission, and intrauterine fetal death (IFD). The secondary outcomes were maternal outcomes, including maternal SARS-CoV-2 infection, cesarean delivery, postpartum hemorrhage, and chorioamnionitis. Results. Nine observational studies involving 81,349 vaccinated (mean age, 32.0 +/-4.6 years) and 255,346 unvaccinated women during pregnancy (mean age, 30.5+/-5.1 years) were included. COVID-19 vaccination during pregnancy was associated with lower risk of NICU admission (OR, 0.88;95% confidence intervals [CI], 0.80-0.97) and IFD (OR, 0.73;95% CI, 0.57-0.94), whereas it was not associated with preterm birth (OR, 0.89;95% CI, 0.76-1.04), SGA (OR, 0.99;95% CI, 0.94-1.04), and low Apgar score (OR, 0.94;95% CI, 0.87-1.02). COVID-19 vaccination during pregnancy was associated with a lower risk of maternal SARS-CoV-2 infection (OR, 0.46;95% CI, 0.22-0.93), but not associated with increased risk of cesarean delivery (OR, 1.05;95% CI, 0.93-1.20), postpartum hemorrhage (OR, 0.95;95% CI, 0.83-1.07), and chorioamnionitis (OR, 0.95;95% CI, 0.83-1.07). Flowchart of study selection Forest plots showing the odds ratio of neonatal outcomes a neonatal intensive care units admission, b intrauterine fetal death, c preterm birth, d small for gestational age, e low Apgar score Forest plots showing the odds ratio of maternal outcomes a maternal SARS-CoV-2 infection, b cesarean delivery, c postpartum hemorrhage, d chorioamnionitis Conclusion. COVID-19 vaccination during pregnancy did not increase the risk of peripartum outcomes but decreased the risk of NICU admission, IFD, and maternal COVID-19 infection. COVID-19 vaccination should be encouraged for pregnant women.