Covid-19 vaccination and pregnancy: a systematic review of maternal and neonatal outcomes

Although the vaccination against Severe Acute Respiratory Syndrome Coronavirus 2 (SARS Cov-2) is considered safe during pregnancy, vaccine hesitancy among pregnant women is high. The results of published observational studies addressing the issue of Covid-19 vaccination's efficacy and safety during pregnancy need to be summarized.

This systematic review compares the incidence of major maternal and neonatal outcomes between SARS Cov-2 vaccinated and unvaccinated pregnant women. The included studies enrolled pregnant women of any age and any trimester. Medline-Pubmed, Scopus, Cochrane Library, and grey literature were searched until the 28th of May 2022, and 2,947 studies were found.

Seven observational cohort studies, enrolling 67,274 pregnant women, were selected. When comparing vaccinated and unvaccinated pregnant women, SARS Cov-2 vaccines were not associated with major maternal and neonatal adverse events. The rate of SARS Cov-2 infections among vaccinated pregnant women compared to unvaccinated is significantly reduced by 43%.

SARS Cov-2 vaccination in pregnant women is effective and safe. The results are promising, but caution is advised due to some limitations: only observational studies addressing this issue were found. Parallelly, the enrolled populations and the intervention (vaccination type and the number of doses) were not homogeneous.