COVID-19 Vaccination During Pregnancy and Birth Defects

Strategic Insights -

Researchers from the Centers for Disease Control and Prevention (CDC) have conducted a study on the prevalence of birth defects among infants born to women who received COVID-19 vaccines during pregnancy. The study, published in Birth Defects Research, analyzed data from the CDC's COVID-19 Vaccine Pregnancy Registry (C19VPR) and found that the prevalence of major birth defects was 3.8%. The researchers compared their findings to pre-pandemic estimates and found that the prevalences were generally similar. However, there was no strong evidence of associations between vaccination and specific defects.

Key Takeaways:

  • The study analyzed data from 19,931 participants in the C19VPR, which enrolled women receiving COVID-19 vaccines in the United States between 2021 and 2022.
  • The prevalence of major birth defects was 3.8%, which is generally similar to pre-pandemic estimates.
  • The study found that the prevalences of birth defects did not differ by the timing of vaccination for seven defects examined.
  • Most participants (65.2%) received their first COVID-19 vaccine after the first trimester, and most received Pfizer-BioNTech (59.0%), Moderna (38.2%), or Janssen (2.8%) vaccines.
  • The study concluded that there was no strong evidence of associations between vaccination and specific defects, but statistical power was low.
  • The study reported that 35 out of 50 defects examined had prevalences below or within expected ranges.
  • The prevalences of birth defects were higher than the comparator confidence interval for 15 defects, but the C19VPR confidence intervals included comparator estimates.
  • The study found that the timing of vaccination did not affect the prevalence of birth defects for seven defects examined.

Statistics:

  • The study analyzed data from 19,931 participants in the C19VPR.
  • The prevalence of major birth defects was 3.8%.
  • 65.2% of participants received their first COVID-19 vaccine after the first trimester.
  • 59.0% of participants received Pfizer-BioNTech vaccines.
  • 38.2% of participants received Moderna vaccines.
  • 2.8% of participants received Janssen vaccines.
  • The study examined 50 defects and found that 35 had prevalences below or within expected ranges.

Sources:

  • Covid-19 Vaccination During Pregnancy and Birth Defects: Results From the Cdc Covid-19 Vaccine Pregnancy Registry, United States 2021-2022. Birth Defects Research, 2025;117(5).
  • NewsRx. New Findings from Division of Healthcare Quality Promotion Describe Advances in COVID-19 (Covid-19 Vaccination During Pregnancy and Birth Defects: Results From the Cdc Covid-19 Vaccine Pregnancy Registry, United States 2021-2022). Medical Letter on the CDC & FDA. June 22, 2025; p 116.