Systematic review and meta-analysis of the effectiveness and perinatal outcomes of COVID-19 vaccination in pregnancy

Abstract

Safety and effectiveness of COVID-19 vaccines during pregnancy is a particular concern affecting vaccination uptake by this vulnerable group. Here we evaluated evidence from 23 studies including 117,552 COVID-19 vaccinated pregnant people, almost exclusively with mRNA vaccines. We show that the effectiveness of mRNA vaccination against RT-PCR confirmed SARS-CoV-2 infection 7 days after second dose was 89 center dot 5% (95% CI 69 center dot 0-96 center dot 4%, 18,828 vaccinated pregnant people, I-2 = 73 center dot 9%). The risk of stillbirth was significantly lower in the vaccinated cohort by 15% (pooled OR 0 center dot 85; 95% CI 0 center dot 73-0 center dot 99, 66,067 vaccinated vs. 424,624 unvaccinated, I-2 = 93 center dot 9%). There was no evidence of a higher risk of adverse outcomes including miscarriage, earlier gestation at birth, placental abruption, pulmonary embolism, postpartum haemorrhage, maternal death, intensive care unit admission, lower birthweight Z-score, or neonatal intensive care unit admission (p > 0.05 for all). COVID-19 mRNA vaccination in pregnancy appears to be safe and is associated with a reduction in stillbirth. Pregnant women have been disproportionately under-vaccinated against COVID-19, partly because they were excluded from initial trials. This systematic review and meta-analysis supports efficacy of vaccination in pregnancy, and finds no evidence of adverse maternal or perinatal outcomes.