NIH announces clinical trial for nasal COVID vaccine

Maternal COVID-19 vaccination during the first trimester of pregnancy is not linked to major structural birth defects, according to a study published yesterday in JAMA Pediatrics.

The study was based on outcomes observed in women who received one or two doses of COVID-19 mRNA vaccine during the first trimester of pregnancy and gave birth between March 5, 2021, and January 25, 2022, at eight U.S. study sites.

Among 42,156 eligible pregnant women, 7,632 (18.1%) received a COVID-19 mRNA vaccine in the first trimester. 524 pregnant women without COVID-19 vaccination in the first trimester, 2,045 (5.9%) were vaccinated before pregnancy, 13,494 (39.1%) in the second or third trimester, and 18,985 (55.0%) were unvaccinated.

No increase in congenital malformations

According to the authors, major structural congenital malformations occurred in 113 infants (1.48%) after COVID-19 mRNA vaccination in the first trimester and in 488 infants (1.41%) without first-trimester vaccine exposure. The adjusted prevalence rate was 1.02 (95% confidence interval, 0.78 to 1.33).

Compared with unvaccinated pregnant women, those vaccinated in the first trimester were older (mean age 32.3 years versus 30.6 years).

No significant differences were identified between vaccinated and unvaccinated infants during the first trimester.

“In secondary analyses, with major structural congenital malformation outcomes grouped by organ system, no significant differences between infants vaccinated or unvaccinated in the first trimester were identified,” the authors said.