OBJECTIVES: We examine associations among race, prepregnancy depressive mood, and preterm birth (<37 weeks gestation) in a cohort study of black and white women.

METHODS: We tested for mediation of the association between race and preterm birth by prepregnancy depressive mood among 555 women enrolled in the Coronary Artery Risk Development in Young Adults (CARDIA) Study.

RESULTS: Black women had significantly higher levels of prepregnancy depressive mood (modified CES-D score 13.0 vs. 9.5, t = -4.64, p < 0.001). After adjustment for covariates, black women had 2.70 times the odds of preterm birth as white women (95% confidence interval [CI] 1.41, 5.17). When adding prepregnancy depressive mood to this model, higher depressive mood was associated with greater odds of preterm birth (odds ratio [OR] 1.04; 95% CI 1.01, 1.07), and the effect of black race was attenuated (OR 2.47, 95% CI 1.28, 4.77).

CONCLUSIONS: Our data suggest that prepregnancy depressive mood may be a risk factor for preterm birth among black and white women.