Racial Differences in the Association Between Maternal Antenatal Depression and Preterm Birth Risk: A Prospective Cohort Study

Background: In the United States, racial/ethnic disparities in preterm birth (PTB) are well documented, but explanations for why the disparity persists remain to be fully explored. We examined racial/ethnic differences in the association of maternal antenatal depression with PTB (<37 completed weeks of gestation) risk. Methods: In a prospective cohort study, participants (n=2073) included non-Hispanic (NH) black, NH white, Asian, and Hispanic women who received prenatal care at a university obstetric clinic January 2004-March 2010, and delivered at the university's hospital. We obtained data from self-reported questionnaires and electronic medical records. We assessed antenatal depression using the Patient Health Questionnaire-9 and self-reported antenatal antidepressant medication use. Poisson regression models were used to estimate the association between antenatal depression and PTB risk, within strata of race/ethnicity. Results: NH black (risk ratio [RR]=1.89; 95% confidence interval [CI]: 0.94, 3.80), NH white (RR=1.58, 95% CI: 1.04, 2.39), and Asian (RR=2.06; 95% CI: 0.69, 6.13) women with antenatal depression were at increased risk for delivering preterm infants, compared with women without antenatal depression, although the associations were statistically significant only among NH white women. There was no evidence of an association between antenatal depression and risk of PTB among Hispanic women (RR=0.96; 95% CI: 0.28, 3.25); p-value for interaction=0.81. Conclusion: Our findings suggest race-specific associations of antenatal depression with an increased risk of delivering a preterm infant, supporting the importance of considering race/ethnicity when examining risk factors for health outcomes.