It's not surprising that someone who is pregnant and getting ready to deliver might become increasingly nervous as they head into a new cold, flu and COVID season. Their concern is not just for their own health, but for that of their unborn children. A recent study from researchers at the University of Toronto offers reassurance.

Babies born to pregnant people who received an mRNA COVID-19 vaccine during pregnancy were less likely to experience severe health outcomes, neonatal death and neonatal intensive care unit (NICU) admission, the study found.

Other studies in Canada have not reported an increased risk of miscarriage or stillbirth in women who received COVID-19 vaccines during pregnancy and they have found a lowered risk of stillbirth.

The health records used in the study included over 142,000 live births in Ontario, Canada, in which the pregnant person had received an mRNA vaccination during pregnancy. The study included deliveries expected between May 1, 2021 and September 2, 2022. Over 85,500 (60 percent) of the infants in the study had been exposed to one or more COVID-19 vaccine doses in utero.

Among the findings:

  • Infants who had been exposed to the vaccine had less risk of severe health outcomes, neonatal death and being admitted to neonatal intensive care, compared to infants who were not exposed to the vaccine.
  • People who were pregnant and vaccinated were more likely to be having their first baby and over 30 years of age. They had received a flu vaccine during either of the two previous influenza seasons, and tended to be residents of urban areas and with higher incomes.

As we head into another viral season, the outlook is good for those who are vaccinated. “Many women feel nervous about receiving vaccines during pregnancy, but our study will hopefully provide some reassurance on the safety of COVID-19 vaccine during pregnancy for newborns and young infants,” researcher Sarah Jorgensen, a pharmacist and PhD candidate at the University of Toronto, said.

Because the study only looked at live births, it could mean that the research did not include the effects of vaccination on miscarriage and stillbirths. However, other studies in Ontario province have not reported an increased risk of miscarriage or stillbirth in women who received COVID-19 vaccines during pregnancy; in fact, they found a lowered risk of stillbirth.

The study is published in JAMA Pediatrics.