Prenatal antidepressants linked to preterm births

Antidepressant drug use during pregnancy, but not depression itself, is associated with an increased risk of preterm birth and lower fetal age at delivery, according to results of a study published in the American Journal of Psychiatry.

"Depressive symptoms are not uncommon during pregnancy, and...symptoms may occur more frequently during pregnancy than in the postpartum period," write Dr. Rita Suri and colleagues from the University of California, Los Angeles. Depression during pregnancy and just after delivery "has been associated with low maternal weight gain, increased frequency of cigarette, alcohol, and substance use, and ambivalence about the pregnancy."

To further investigate, the researchers examined the effects of maternal depression and antidepressant drug use on fetal age and risk of preterm birth in a study of 90 pregnant women.

The women were divided into three groups: 49 women had major depressive disorder and were treated with antidepressant medication for more than 50 percent of their pregnancy; 22 women had major depressive disorder and were briefly treated or not treated with antidepressants during pregnancy; and a comparison group of 19 healthy pregnant women.

The average fetal age at birth was 38.5, 39.4, and 39.7 weeks in the three groups, respectively. The groups also differed in the rates of preterm birth (14.3 percent, 0 percent, and 5.3 percent) and rates of admission to the special care nursery (21 percent, 9 percent, and 0 percent).

No significant between-group differences were observed in actual infant birth weights or Apgar scores.

Based on these findings, the presence of depression per se during pregnancy did not adversely affect outcomes. "This result was surprising to us, as we had anticipated that depression and anxiety during pregnancy would be associated with an increased risk of preterm birth," Suri and colleagues write.

"The two groups of women with depression - those who were treated with antidepressants and those who were not - had similar degrees of depression and anxiety during pregnancy," they note.

These findings suggest that antidepressant use, rather than mild-to-moderate depression, was associated with lower fetal age and an increased risk of preterm birth.

SOURCE: American Journal of Psychiatry, August 2007.