Burden of stillbirths among women vaccinated with COVID-19 vaccines: A systematic review and meta-analysis

Objective: To estimate the global burden of stillbirths among pregnant women with the COVID-19 vaccination. Data source: In this systematic review and meta-analysis, a literature search was carried out in PubMed, Cochrane and Scopus until February 4, 2023, with language restriction (English). Study selection: Title-abstract screening followed by full text review was done independently by two authors, based on the research question, “What is the prevalence of stillbirths among the pregnant women vaccinated with COVID-19 vaccines?” Data extraction: Two authors independently extracted the relevant data from every study. The third author resolved the conflicts. This study was registered in PROSPERO and followed the PRISMA guidelines. Data analysis: A Random effects model was applied to assess the pooled estimate of stillbirths. The I2 test was used to assess the heterogeneity of the articles included in the study. For checking the publication bias, the Doi plot and the contour-enhanced funnel plot were utilized. Results: The database systematic search yielded 168 articles; 11 of them were determined to be eligible for systematic review and 8 of them ended up being included for meta-analysis. The pooled prevalence of stillbirth in pregnant women vaccinated against COVID-19 infection was 0.00509 (5 per 1000 live births delivered by pregnant women vaccinated against COVID-19 (95% CI: 0.00003–0.01676). Statistically significant heterogeneity was reported across studies (I2 = 98%; p < 0.01). Conclusions: The study concluded that vaccination against COVID-19 among pregnant women had a low stillbirth rate. It adds to the existing evidence that the COVID-19 vaccine is safe and can be taken during pregnancy.