Birth defect risk from antidepressants low: studies

By Gene Emery

BOSTON (Reuters) - Newer antidepressant drugs may increase the risk of birth defects but the risk remains very remote, according to two new studies published on Thursday.

The drugs, known as selective serotonin reuptake inhibitors or SSRIs, may cause a very small increase in the number of heart defects, but even this is unclear, researchers report in this week's issue of the New England Journal of Medicine.

"Researchers, did, however, find associations between SSRI use and three specific birth defects: a defect of the brain, one type of abnormal skull development and a gastrointestinal abnormality," the U.S. Centers for Disease Control and Prevention said in a statement.

"CDC plans to continue to study the association to clarify whether a true risk exists," it added.

"Any increased risks of these malformations in association with the use of SSRIs are likely to be small in terms of absolute risks," Dr. Michael Greene of Massachusetts General Hospital wrote in a commentary.

About 10 percent of pregnant women suffer from depression, according to the March of Dimes. The CDC says every pregnancy has a 3 percent risk of a major birth defect, regardless of exposures.

Concern over SSRIs surfaced nearly two years ago when a survey of 527 fetuses whose mothers took GlaxoSmithKline's Paxil during their first three months of pregnancy found that 4.4 percent were born with major malformations, usually of the heart.

The rate was 2.2 percent among women taking other antidepressants.