Association of COVID-19 vaccination during pregnancy with COVID-19 risk in infants

Editor's Note

This Norwegian study finds that maternal COVID-19 vaccination during the second or third trimester of pregnancy was associated with a reduced risk of COVID-19 within the first 4 months of life of their infants.

Of 21,643 infants analyzed, 9,739 (45%) were born to women who received a second or third dose of a COVID-19 vaccine during pregnancy.

The first 4 months of life incidence rate of a positive COVID-19 test was 5.8 per 10,000 follow-up days.

Infants of mothers vaccinated during pregnancy had a lower risk of a positive COVID-19 test compared with infants of unvaccinated mothers, during the Delta period (1.2 vs 3.0 per 10,000 follow-up days) and the Omicron period (7.0 vs 10.9 per 10,000 follow-up days).

The researchers conclude that maternal COVID-19 vaccination may provide passive protection to young infants, for whom vaccines are not currently available.