Paroxetine in the first trimester and the prevalence of congenital malformations

To refine a preliminary analysis identifying a possibly increased prevalence of malformations among infants born to women exposed to paroxetine in the first trimester.

This study used data from UnitedHealthcare, a large U.S. insurer, using datasets originally for a study of bupropion in pregnancy. We identified women with a live-born delivery between January 1995 and September 2004. We classified women according to their first trimester mono- or mono/polytherapy exposure to paroxetine and other antidepressants. We confirmed malformation cases by medical record abstraction. We calculated the adjusted odds ratios (AORs) through logistic regression.

For paroxetine, there were 815 infants among 791 women exposed as monotherapy, and 1020 infants among 989 women exposed as mono- or polytherapy. For other antidepressants, there were 4198 infants among 4072 women exposed as monotherapy, and 4936 infants among 4767 women exposed as mono- or polytherapy. AORs for all congenital malformations associated with paroxetine were 1.89 (95%CI 1.20-2.98) for monotherapy, and 1.76 (95%CI 1.18-2.64) for mono- or polytherapy. AORs for cardiovascular malformations associated with paroxetine were 1.46 (95%CI 0.74-2.88) for monotherapy, and 1.68 (95%CI 0.95-2.97) for mono- or polytherapy.

These more detailed paroxetine findings confirm previous findings of analyses of these data among women exposed to all types of antidepressants. The present findings are consistent with other recent results suggesting the possibility of a modestly increased occurrence of congenital malformations following first trimester exposure to paroxetine compared to other antidepressants.