Does antidepressant use attenuate the risk of a major depressive episode in pregnancy?

Many women become pregnant while undergoing antidepressant treatment and are concerned about continuing antidepressant medication. However, antidepressant discontinuation may increase the risk of a new episode of major depressive disorder. We sought to estimate differences in the risk of developing a new major depressive episode among pregnant and postpartum women with recurrent illness who either did or did not use antidepressants.

Participants were recruited from obstetrical settings; we analyzed a subgroup of 778 women with a history of a depressive disorder. Diagnoses were determined by the Composite International Diagnostic Interview administered twice in pregnancy and once after delivery. We used Cox Regression to model onset of a major depressive episode with a time-dependent predictor of antidepressant use.

There was no clear difference in risk of a major depressive episode between women who took antidepressants and women who did not (hazard ratio [HR] = 0.88; 95% CI = 0.51-1.50). After accounting for antidepressant use, clearly hazardous factors included 4 or more depressive episodes before pregnancy (HR = 1.97; 95% CI = 1.09-3.57), black race (HR = 3.69; 95% CI = 2.16-6.30), and Hispanic ethnicity (HR = 2.33; 95% CI = 1.47-3.69).

Failure to use or discontinuation of antidepressants in pregnancy did not have a strong effect on the development of a major depressive episode. Women with 4 or more episodes before pregnancy were at high risk of a major depressive episode, independent of antidepressant use. Black and Hispanic women also were at high risk of a major depressive episode, but it is possible that this effect is attributable to unmeasured factors.