Study finds COVID-19 vaccination during pregnancy does not increase complications around the time of childbirth

Researchers have found that receiving a COVID-19 vaccine during pregnancy does not lead to increases in the frequency of complications around the time of childbirth. The findings, which are published in JAMA, provide further assurances about the safety of mRNA vaccines for this particularly unique population.

Lead author Dr. Deshayne Fell led the study of nearly 100,000 pregnancies by analyzing data from BORN Ontario (Ontario's provincial birth registry), which is linked to the province's COVID-19 immunization database.

While analyzing childbirths between December 2020 and September 2021, Dr. Fell found:

• Approximately 23 percent (over 22,000 individuals) received at least one dose of a COVID-19 vaccine during pregnancy.
• No increase in the babies' need for neonatal intensive care unit (NICU) admission.
• No frequency of low Apgar scores (an assessment at birth that can identify babies who may need special care, such as extra help with their breathing) in babies born to vaccinated mothers, compared to babies born to unvaccinated mothers.
• Vaccination was not associated with increased risk of:
  • heavy bleeding after childbirth;
  • infection in the uterus or membrane;
  • emergency cesarean section among the vaccinated mothers, compared to unvaccinated mothers.

"There is increasing evidence from studies around the world showing that COVID-19 vaccination during pregnancy is not associated with poor pregnancy or birth outcomes, and showing that COVID-19 vaccines are effective at preventing COVID-19 in pregnant mothers and also in their babies in the first few months of life," says Dr. Fell, an Associate Professor in the University of Ottawa's Faculty of Medicine and a Scientist at the CHEO Research Institute.

Vaccination against COVID-19 is recommended for pregnant individuals since they are at a higher risk of complications from the disease, including hospitalization, ICU admission and death, compared with nonpregnant individuals. COVID-19 during pregnancy has also been linked with increased risks of pregnancy complications such as preterm birth of the babies.