Use of antidepressants late in pregnancy may be associated with an increased risk of babies born with a serious respiratory disorder, but the increased risk appears to be less than previous research has suggested, according to a new study.

The new research provides additional data for patients and doctors to consider, though it doesn’t give the total clarity many pregnant women would probably like.

The study focused on persistent pulmonary hypertension of the newborn, or PPHN, which is marked by severe respiratory failure. In 2006, the U.S. Food and Drug Administration warned that the most common type of antidepressant—selective serotonin reuptake inhibitors, or SSRIs—could be linked to PPHN, after one study showed a sixfold increased risk associated with SSRI use. But further studies reported conflicting results, causing the FDA to revise its guidance in 2011 to say it is “unclear” whether SSRIs are linked to the disorder.

The latest study, published by the Journal of the American Medical Association, examined the medical records of 3.8 million Medicaid patients who gave birth between 2000 and 2010, comparing PPHN cases in women who took antidepressants during their final trimester to those who didn’t take any antidepressants during pregnancy.

The study found the absolute number of PPHN cases was low—there were 20.8 cases per 10,000 births in babies who weren’t exposed to antidepressants, versus 31.5 in babies exposed to SSRIs and 29.1 in babies exposed to other types of antidepressants.

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