A new study adds to the growing body of literature demonstrating the safety of COVID-19 vaccine use in pregnant women. The study, published in BMJ, showed no connection between COVID vaccination or infection in the first trimester of pregnancy and congenital birth defects.
The study is based on outcomes seen among 343,066 live-born single infants in Sweden, Denmark, and Norway with an estimated first trimester of pregnancy occurring from March 1, 2020, to February 14, 2022. The infants were followed up for at least 9 months after birth.
In the entire cohort, 17,704 infants (5.2%) had a major congenital anomaly, or 516 per 10,000 live births. Congenital anomalies included congenital heart defects; nervous system anomalies; eye anomalies; ear, face and neck anomalies; respiratory anomalies; oro-facial clefts; gastrointestinal anomalies; abdominal-wall defects; congenital anomalies of the kidney and urinary tract; genital anomalies; and limb anomalies.
No observed risk for COVID-19 infections
A total of 10,229 infants (3% of the total) were exposed to COVID-19 infections during the first trimester of pregnancy. There was no increased risk for congenital defects associated with infection, with an adjusted odds ratio of 0.96 (95% confidence interval [CI], 0.87 to 1.05).
In general, first-trimester infections with COVID-19 were associated with mothers who had more children, lower educational level, and lower household income level, and were born in the Middle East or Africa.
The authors found that 29,135 of 152,261 infants (19%) included in a vaccination analysis were exposed to COVID-19 vaccination during the first trimester. All vaccines were two-dose mRNA vaccines.
"Mothers vaccinated against COVID-19 during the first trimester had higher education and household income, were more likely to have an underlying chronic disease, and were more likely to be overweight or obese," the authors said.
The authors found no significant increased risk of any major congenital anomaly among infants whose mothers were vaccinated against COVID-19 during the first trimester, with an adjusted odds ratio of 1.03 (95% CI, 0.97 to 1.0).
Overall, our findings support the current recommendations to vaccinate pregnant women against COVID-19.
"We add to the current evidence with our results showing that there appears to be no robust evidence of an increased risk of any of the subgroups of congenital anomalies," the authors concluded. "Overall, our findings support the current recommendations to vaccinate pregnant women against COVID-19."