Approximately 1-in-10 women who have COVID-19 during pregnancy will develop long COVID, according to new data presented at the Society for Maternal-Fetal Medicine’s (SMFM) annual meeting (The Pregnancy Meeting).

Researchers followed a group of individuals from 46 states plus Washington DC, who got COVID while pregnant to see whether they developed long COVID and, if so, what factors put people at greater risk. The pregnancy cohort is part of a larger study, the NIH RECOVER Initiative, that aims to learn more about the longterm effects of COVID in adults and children.

Of the 1,503 people in the pregnancy cohort, slightly more than half (51%) were fully vaccinated before contracting COVID; and the average age at infection was about 32 years old. The study looked at a person’s pre-existing conditions, socioeconomic status, and severity of COVID during pregnancy.

Researchers found that 9.3% of pregnant people developed long COVID when evaluated six months or more after their initial infection. The most common symptoms people reported included feeling worn out after even minor physical or mental activity, also known as post-exertional malaise, fatigue, and dizziness.

Researchers also found that pregnant people who were obese or suffered from depression or chronic anxiety, as well as those who reported having difficulty paying their bills were all at greater risk of developing long COVID. People who had a more severe case of COVID and required oxygen while pregnant were also at higher risk of developing long COVID.

“The key takeaway for clinicians who are taking care of pregnant patients is that nearly 1-in-10 people who have COVID during pregnancy still have persistent symptoms six months later,” says the study’s lead author Torri D. Metz, MD, MS, a maternal-fetal medicine subspecialist and associate professor of obstetrics and gynecology at the University of Utah Health in Salt Lake City. 2 “The trimester of infection was not associated with the development of long COVID, so it did not seem to matter when in their pregnancy people were infected.”

Researchers also compared their findings to the larger NIH RECOVER-Adult cohort findings, which includes non-pregnant people, and discovered that the rate of long COVID appeared to be lower in pregnant people than in non-pregnant adults.

“That could be due to a number of reasons that are worth investigating in the future,” notes Metz. An important next step and one that is already in progress, say researchers, is to look at the outcomes of the infants of pregnant people who developed long COVID. The abstract was published in the January 2024 supplement of the American Journal of Obstetrics and Gynecology.