Antidepressant use during pregnancy and the risk of preterm delivery and fetal growth restriction

The associations between prenatal exposure to antidepressants and preterm delivery and fetal growth restriction are controversial and poorly understood. We studied the relation between antidepressant use and these outcomes.

Analysis included women with nonmalformed infants interviewed in the Slone Epidemiology Center Birth Defects Study between 1998 and 2008. We estimated odds ratios (ORs) and 95% confidence intervals (CIs) for premature and small-for-gestational age (SGA) offsprings, adjusting for sociodemographic, lifestyle, medical, and reproductive factors.

The frequencies of preterm delivery were 7.3% among the 5710 nonusers (reference), 8.9% among the 192 selective serotonin reuptake inhibitor (SSRI) users (OR, 1.1; 95% CI, 0.6-2.0), and 15.3% among the 59 non-SSRI antidepressant users (OR, 2.2; 95% CI, 1.0-4.9); the respective frequencies of delivering an SGA offspring were 7.2%, 10.9% (OR, 1.7; 95% CI, 1.0-2.7), and 13.6% (OR, 2.2; 95% CI, 1.0-4.9). Compared with nonusers, the frequencies of preterm delivery (7.6%) and SGA offspring (5.7%) were not increased among the 106 women who discontinued SSRIs before the end of the first trimester. Among women who continued SSRIs beyond the first trimester, 10.5% delivered a preterm infant (OR, 1.3; 95% CI, 0.6-2.8) and 17.4% had an SGA offspring (OR, 3.0; 95% CI, 1.7-5.5).

Women treated with SSRIs late in pregnancy had a higher frequency of delivering SGA infants, and women receiving non-SSRI antidepressants were more likely to deliver premature and SGA offsprings. The findings suggest an effect of underlying mood disorder or an effect common to both drug classes. In any case, prenatal antidepressant use may help identify women at elevated risks of delivering preterm and SGA infants.