COVID-19 Vaccination Not Linked to Major Structural Birth Defects

FRIDAY, March 14, 2025 (HealthDay News) — COVID-19 vaccination in early pregnancy (≤20 weeks of gestation) is not associated with increased prevalence of major structural birth defects, according to a study published online March 14 in Pediatrics.

Stacey L. Rowe, Ph.D., M.P.H., from the University of San Francisco, and colleagues compared the prevalence of major structural birth defects by COVID-19 vaccination status and compared the prevalence by brand (Moderna mRNA-1273 versus Pfizer-BioNTech BNT162b2) in a claims-based cohort study. Pregnancies ending in a live birth were captured among people with an estimated last menstrual period between Aug. 15, 2021, and Dec. 24, 2021.

The researchers identified 1,248 major structural birth defects among 78,052 pregnancies: 1,049 in unvaccinated people and 199 in vaccinated people (160.6 and 156.4 per 10,000 live births, respectively). There were no significant differences in the prevalence of major structural birth defects based on COVID-19 vaccination status. No change was seen in the findings by insurance provider, severe acute respiratory syndrome coronavirus 2 infection during pregnancy, or concomitant administration of other maternal vaccines. Among vaccinated people, no differences were seen in the prevalence of birth defects by brand.

“Our findings align with other comparable studies and provide reassurance to potential vaccinees and vaccine providers considering COVID-19 vaccination early in pregnancy,” the authors write.

Two authors disclosed ties to pharmaceutical companies, including Moderna and Pfizer.

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