A recent study of nearly 200,000 newborns in Sweden and Norway found no risk to infants from COVID-19 vaccines given during pregnancy. The study, published in JAMA, even found that babies born to vaccinated mothers had a lower risk of serious complications and a lower mortality rate. However, the reason for this lower risk is not yet clear.
Mikael Norman, PhD, the study’s first author, said that the vaccine itself is unlikely to be the cause. Previous studies have shown that the vaccine does not cross the placenta. Yet, the lower risk of death among infants of vaccinated women is a consistent finding.
The study used data from the national birth registry. It included births from the 22nd week of pregnancy onwards, after COVID-19 vaccines became available. The babies in the study were born between June 2021 and January 2023. Almost half of the mothers had received at least one dose of a COVID-19 vaccine during pregnancy.
The study also found that babies born to vaccinated mothers had a lower risk of certain serious health conditions. There were no cases of heart inflammation or low platelet count, and no increased risk of breathing problems or severe intestinal disease.