Around one in ten women infected with Covid-19 during pregnancy are expected to develop long-term Covid symptoms, according to research presented at the annual meeting of American Society for Maternal-Fetal Medicine.

The researchers watchedn a group of women from 47 states, who contracted Covid-19 during pregnancy, to see if they developed long Covid and, if so, what factors put them at greater risk.

Of the 1,503 women followed, just over half were fully vaccinated before contracting Covid, and the average age at infection was about 32. It found that 9.3% of women developed long Covid when assessed six months or more after their initial infection. The most common symptoms they reported included feeling exhausted, even after little physical or mental activity, fatigue and dizziness.

Also, the researchers found that pregnant women who were obese or suffered from depression or chronic stress, were at greater risk of developing long-term Covid. Those who developed more severe disease and required oxygen during pregnancy were also at higher risk of developing long-term Covid.

When they compared their findings with the findings of a larger database of people – not pregnant – the researchers found that the rate of long Covid appeared to be lower in pregnant women than in other adults. “This could be for a number of reasons that are worth investigating in the future,” notes study lead author and associate professor of Obstetrics and Gynecology at University of Utah Health Sciences Tori Metz. She emphasizes that “trimester of infection was not associated with long-term development of Covid, so it does not seem to matter when in pregnancy they were infected.”