New research continues to affirm the safety of the covid-19 vaccines for people planning or expecting to have children. The study found no evidence that vaccination affected the outcomes of patients getting in-vitro fertilization (IVF), either in their chances of becoming pregnant or experiencing complications like an early miscarriage.
The research was a joint effort by researchers at the Icahn School of Medicine at Mount Sinai and Reproductive Medicine Associates (RMA) of New York, an organization that operates many fertility clinics in the area.
The team examined two sets of about 1,000 patients each: those who underwent a frozen-thawed embryo transfer, where a person’s embryos, fertilized in the lab, are kept in storage then implanted in the womb later, and those who had ovarian stimulation, which is used to produce as many mature eggs as possible for future attempts at IVF. Among these groups, the researchers compared patients who were unvaccinated and vaccinated with two doses of an mRNA vaccine.
Overall, the team found nothing but good news. For those who had their embryos implanted, the rate of a successful pregnancy was the same between vaccinated and unvaccinated individuals, and there was no difference in the risk of an early pregnancy loss. And for those who had their ovaries stimulated, the number of eggs that could be harvested, their odds of a successful fertilization, and the development of healthy embryos, among other measures, was the same regardless of vaccination status.
Studies in the past have looked at the possible connection between covid-19 vaccination and fertility and have similarly found no negative effects from the vaccines. But study author Erkan Buyuk, a reproductive endocrinologist and infertility specialist at RMA, notes that many of these studies are based on small sample sizes. As far as the team knows, theirs is the largest study to fully capture the effect of covid vaccines on fertilization and implantation rates during IVF, as well as on early pregnancy losses, which often go unnoticed, she said. The team’s takeaway from their findings, published Tuesday in the journal Obstetrics & Gynecology, is clear.
“Vaccination with covid mRNA vaccines doesn’t affect the success rates obtained from assisted reproductive technology treatments,” Buyuk told Gizmodo in an email.
While 75% of the U.S. population has received at least one vaccine dose, rates among pregnant people have remained lower. Some of this hesitancy is due to misguided beliefs about the risks of vaccination and the risks posed by covid-19 during pregnancy in general. Other evidence has shown, for instance, that pregnant people who contract covid-19 are at higher risk of severe illness and of developing complications like stillbirth. So Buyuk and her team hope their latest research can reassure people still on the fence, particularly those considering IVF.
These patients, Buyuk said, “should not hold their vaccinations for fear of affecting their success from these treatments or for fear of affecting their pregnancy.”