More than four years after the virus that causes COVID first appeared, scientists continue to discover new ways that the illness threatens pregnant people and babies—as well as additional evidence that vaccination offers significant protection.
A new study finds that babies born to women who got COVID while they were pregnant were three times more likely to develop serious breathing problems than infants whose mothers didn’t have the disease during pregnancy, even if the infants weren’t infected themselves. Seventeen percent of the babies in the study who were exposed to COVID before birth developed respiratory distress, compared with only about 5 to 6 percent of newborns in the general population before the pandemic. The findings were published on Wednesday in Nature Communications.
Respiratory distress is a serious and sometimes life-threatening complication that can lead babies to be hospitalized in intensive care units, where they’re given extra oxygen or even placed on a ventilator. In the study, babies with respiratory distress were sick for an average of 24 days. None died. The researchers followed the infants for six months and don’t know if any of the babies had longer-term complications.
Respiratory distress is most often seen in premature babies whose lungs aren’t fully developed, says Karin Nielsen, the study’s senior author and a professor of pediatrics who specializes in infectious diseases at the David Geffen School of Medicine at the University of California, Los Angeles.
In this study, however, even full-term infants were more likely to develop breathing problems if their mother had COVID while pregnant.
“It’s just one more thing to worry about with this mysterious virus,” says Sean O’Leary, chair of the American Academy of Pediatrics’ Committee on Infectious Diseases, who was not involved in the new study. “Four years in, we’re learning still new things about this virus.”