BACKGROUND: There are limited data regarding COVID-19 vaccination during pregnancy. OBJECTIVES: To evaluate the effects of COVID-19 vaccination received during pregnancy on SARS-CoV-2 infection, COVID-19-related hospitalisation, COVID-19-related ICU admission and maternal-fetal complications. SEARCH STRATEGY: MEDLINE, CINHAL, Embase, Scopus, CENTRAL databases; ClinicalTrials.gov, reference lists, related articles and grey literature sources. SELECTION CRITERIA: Randomised controlled trials, non-randomised studies of interventions, pregnant women, COVID-19 vaccination during pregnancy. DATA COLLECTION AND ANALYSIS: Study selection, risk of bias assessment, data extraction and assessment of the certainty of evidence using the GRADE method were performed independently by two authors. Meta-analyses were performed using Cochrane RevMan version 5.4 software. PROSPERO registration number: CRD42022308849. MAIN RESULTS: We included 14 observational studies (362,353 women). Administration of a COVID-19 vaccine during pregnancy resulted in a statistically significant reduction in SARS-CoV-2 infection [OR: 0.46; 95% CI: 0.28-0.76] and COVID-19-related hospitalisation [OR: 0.41; 95% CI: 0.33-0.51]. The effect appeared to be greater in fully vaccinated women, for both infection [OR: 0.31; 95% CI: 0.16-0.59] and hospitalisation [OR: 0.15; 95% CI: 0.10-0.21]. However, the certainty of evidence was very low. The difference in COVID-19-related ICU admission between vaccinated and unvaccinated individuals did not reach statistical significance [OR: 0.58; 95% CI: 0.13-2.58]. Finally, there were no statistically significant differences in any of the maternal-fetal complications considered in the included studies. CONCLUSIONS: COVID-19 vaccination administered during pregnancy seems to reduce SARS-CoV-2 infection and COVID-19-related hospitalisation, with no significant effects on maternal-fetal complications.
- Pregnant women