Two research studies published today in The New England Journal of Medicine found taking SSRIs (selective serotonin reuptake inhibitors), anti-depression drugs, during pregnancy did not significantly increase the overall risk for most birth defects. However, each study found that taking SSRIs during pregnancy was associated with a small increase in the risk of certain rare birth defects – but they were different birth defects.

Dr. Michael Katz, acting Medical Director of the March of Dimes, said the studies show how important post-market surveillance is in assessing the safety of medications in pregnancy. During pre-approval, drugs are tested on relatively few subjects and only side effects with a large frequency are detected. Once approved, many people take the medication and even very rare side effects surface.

“Most prescription drugs are not tested on pregnant women,” said Dr. Katz. “So we must start monitoring the effects of these medications as soon as they reach consumers, and keep monitoring for as long as it takes to get good data on risks to mothers and babies.”

The March of Dimes recommends women discuss the potential risks and benefits of taking SSRIs during pregnancy with their doctors. Women who are taking an antidepressant should not stop taking their medications if they discover they are pregnant, but should immediately contact their health care provider. It may be dangerous to stop taking an antidepressant suddenly.

About 10 percent of pregnant women in the United States suffer from depression, some of it undiagnosed.

Previous studies have found that some SSRIs may increase the risk for other problems for babies, including:

- Withdrawal symptoms in newborns;

- Pulmonary hypertension of the newborn (PPHN), a rare, but serious heart and lung disorder;

- Low birthweight or preterm delivery.

One study was led by researchers at the University of British Columbia and the National Center on Birth Defects and Developmental Disabilities and the other by researchers at Boston University’s Slone Epidemiology Center.

Source: March of Dimes