The U.K.’s Medicines and Healthcare Products Regulatory Agency (MHRA) found this month that “there is no pattern … to suggest that any of the COVID-19 vaccines used in the UK increase the risk of congenital anomalies or birth complications. Pregnant women have reported similar suspected reactions to the vaccines as people who are not pregnant.”

If infected with the virus, pregnant people are at highly increased risk for severe disease and complications from COVID-19, compared with their same-age counterparts, says Tara Shirazian, an associate professor and a gynecologist at NYU Langone Health.

The immune system effects of pregnancy itself make an infection about five times more likely, says Jane Frederick, a reproductive endocrinology and fertility specialist and medical director of HRC Fertility in California. “You get infected more quickly, and pregnant women can go downhill fast,” she adds.