Rates of Spontaneous and Therapeutic Abortions Following Use of Antidepressants in Pregnancy: Results From a Large Prospective Database

Objective: The use of antidepressants during pregnancy remains a controversial issue, and there is little information on the risk of spontaneous abortions following antidepressant exposure in early pregnancy. We sought to examine whether use of antidepressants increases the rates of spontaneous abortion (SA) and therapeutic abortion (TA) in women exposed in early pregnancy. Methods: In a cohort of women who contacted the Motherisk program during pregnancy, we compared two groups of women, one exposed and the other not exposed to antidepressants during pregnancy, and calculated the associated rates of SA and TA. Results: Among 937 women exposed to antidepressants prior to and during early pregnancy, there were 122 SAs (13.0%) including three ectopic pregnancies, and in the comparison group there were 75 SAs (8.0%) and no ectopic pregnancies. The relative risk was 1.63 (95% CI 1.24-2.14). Three-fold more women reported a TA in the exposed group, 26 (2.4%) compared to 8 (0.7%) in the non-exposed group (RR 3.25; 95% CI 1.48-7.14). A sub-analysis revealed that in both groups, of 338 women with a prior SA, 58 (17.2%) reported having a SA in the current pregnancy, compared with 61/652 (9.4%) with no prior SA (χ2 = 12.09, P < 0.001). In the antidepressant group, the incidence was 20.7%, and in the non-exposed group, it was 13.3%. Logistic regression confirmed that only antidepressant exposure and prior SA were significantly associated with current SA. Conclusion: Exposure to antidepressants in the first trimester of pregnancy appears to be associated with a small but statistically significant increased risk of SA and decision to terminate a pregnancy. The risk for SA is further elevated with a history of previous SA. However, any underlying depression must be taken into consideration when evaluating these results.