Getting vaccinated against COVID-19 does not reduce a couple’s chances of getting pregnant—but contracting the virus might lower male fertility, according to a new study.
Researchers at the Boston University School of Public Health published their findings in the American Journal of Epidemiology. They found no link between COVID-19 vaccination and fertility in either men or women, even when accounting for different vaccine types, such as Pfizer-BioNTech, Moderna, and Johnson & Johnson.
“Many people of reproductive age have expressed concerns about the vaccine affecting fertility,” said Amelia Wesselink, the study’s lead author and a research assistant professor of epidemiology. “Our study is the first to show that vaccination in either partner does not impact fertility among couples trying to conceive through intercourse.”
The research team analyzed data from the Pregnancy Study Online (PRESTO), an ongoing study funded by the National Institutes of Health. PRESTO follows people trying to get pregnant from before conception through six months after delivery.
This particular analysis included 2,126 women in the U.S. and Canada. Participants shared information about their health, lifestyle, and vaccination status from December 2020 to November 2021. The researchers compared fertility rates—defined as the probability of conception per menstrual cycle—between vaccinated and unvaccinated participants.
Results showed nearly identical fertility rates in vaccinated and unvaccinated women. The same was true for male partners who had received at least one vaccine dose. Additional factors like the number of doses, vaccine brand, infertility history, and geographic location also showed no effect on fertility.
However, the study did find that men who had tested positive for COVID-19 within the previous 60 days had lower fertility compared to men who either never had COVID-19 or had recovered more than 60 days earlier. This aligns with earlier research showing that COVID-19 can negatively affect sperm quality and male reproductive health.
“These findings provide strong evidence that vaccination does not impact fertility,” said Lauren Wise, senior author and professor of epidemiology. She emphasized the study’s strengths, including its large sample size, prospective design, and detailed data collection on vaccination and other relevant factors.
The researchers are also analyzing whether COVID-19 vaccines may affect menstrual cycles. While some women have reported changes to their periods after vaccination, Wise noted that their current findings suggest these changes do not impact fertility. Results from that part of the study are expected later this spring.
Wise encouraged those planning a family to get vaccinated, citing numerous studies that show COVID-19 infection can lead to worse outcomes during pregnancy and childbirth.
“There’s strong evidence that COVID infection can harm pregnancy and birth outcomes,” she said. “When we look at all the data, it supports getting vaccinated.”
Related Topics: