The Safety of mRNA COVID-19 Vaccine in the First Trimester of Pregnancy

A recent retrospective cohort study conducted across multiple sites found that receiving an mRNA COVID-19 vaccine during the first trimester of pregnancy did not increase the risk of major structural birth defects in infants. The study, led by Elyse Kharbanda, MD, MPH, from the HealthPartners Institute in Bloomington, Minnesota, reported that there was no significant difference in the occurrence of major structural birth defects between infants born to mothers who received the vaccine in the first trimester and those who did not.

The researchers concluded that these findings should offer reassurance to pregnant individuals and their healthcare providers regarding the safety of receiving an mRNA COVID-19 vaccine during the first trimester. The study, which utilized data from various Vaccine Safety Datalink sites, aimed to address concerns about potential risks associated with first-trimester vaccinations and birth defects.

It is already well-documented that contracting COVID-19 during pregnancy can lead to an increased risk of complications and adverse outcomes for both the pregnant person and the baby. Given this, organizations such as the American College of Obstetricians and Gynecologists recommend COVID-19 vaccination for pregnant individuals at any stage of pregnancy.

The study also examined the prevalence of specific types of birth defects among infants born to mothers who received the mRNA COVID-19 vaccine during the first trimester. While cardiac defects were the most common type of birth defect in both vaccinated and unvaccinated groups, there were no significant differences in the rates of these defects between the two groups.

Study Methodology and Limitations

The retrospective cohort study included data from multiple health systems across several states and compared pregnant individuals who received one or two doses of the mRNA COVID-19 vaccine in the first trimester with those who were either unvaccinated or received the vaccine at a different time. However, the study had some limitations, such as the exclusion of pregnancies that did not result in live births and the lack of information on folic acid use.

Implications for Vaccine Safety

Overall, the findings of this study contribute to the growing body of evidence supporting the safety of mRNA COVID-19 vaccination for pregnant individuals and their babies. Healthcare providers, including obstetricians and gynecologists, can use this information to educate and reassure pregnant patients who may have concerns about the safety of receiving the COVID-19 vaccine during pregnancy. Further research and monitoring are crucial to continue evaluating the long-term effects of COVID-19 vaccination during pregnancy.