N3C-Driven Study Shows COVID-19 Vaccination Did Not Boost Risk of Poor Pregnancy Outcomes

Doctor gives COVID-19 vaccine injection to pregnant person (Shutterstock, Marina Demidiuk).

April 11, 2024

Using data from the National COVID Cohort Collaborative (N3C), researchers found COVID-19 vaccination in pregnant people wasn’t linked to greater risk of early births or stillbirths. The study included electronic health records from 52 health centers across the country. Those records showed vaccination may help prevent early birth.

Earlier studies showed that COVID-19 vaccination during pregnancy lowered the risk of infection and of severe COVID-19 in pregnant people and their babies. In this study, researchers at the University of Minnesota and their colleagues used N3C data to look for links between COVID-19 vaccination and poor pregnancy outcomes.

The researchers looked at four groups of pregnant people:

• Those who were vaccinated before pregnancy.
• Those who were vaccinated during pregnancy.
• Those who were vaccinated after pregnancy.
• Those who were not vaccinated.

They compared people who were vaccinated while they were pregnant to people who were vaccinated when they were no longer pregnant and to those who did not get vaccinated.

The researchers looked at 311,057 people who were more than 20 weeks pregnant. The study showed that 4.6% of those who were vaccinated while pregnant gave birth early. The early birth rate was 5.9% for those who were vaccinated after pregnancy. It was 5.8% among those who were not vaccinated. The rate of stillbirth was 0.4% for people who were vaccinated while pregnant and people who were vaccinated after pregnancy. It was 0.7% for those who were not vaccinated.

The study authors said the findings highlight the safety and importance of COVID-19 vaccination for pregnant people even though the public health emergency has ended.

Learn more about the study findings in Vaccines.