Effects of Stress and Nativity on Maternal Antenatal Substance Use and Postnatal Mental Disorders.

Background: Maternal substance use and common mental disorders (CMDs) during or after pregnancy can lead to negative health outcomes among mothers and infants. We examined whether nativity (US-born versus foreign-born) and stress levels during pregnancy were associated with antenatal substance use and postnatal CMDs. Methods: We analyzed the Boston Birth Cohort, a racially diverse cohort recruited at birth with rolling enrollment since 1998. Information on antenatal substance use (tobacco and/or alcohol use) was obtained using an in-person postpartum questionnaire (n = 6,514). Information on postnatal CMDs (depression and/or anxiety) was obtained from medical records (n = 2,052). Nativity and stress during pregnancy were self-reported. We performed multivariate logistic regression to examine how nativity and stress levels were jointly associated with antenatal substance use and postnatal CMDs. We further investigated if blacks, Hispanics, and whites were differentially at risk. Results: We found that US-born mothers were at higher risk of substance use and CMDs than their foreign-born counterparts. In analyses combining nativity and stress, being US-born with high stress was associated with increased odds of antenatal substance use (adjusted odds ratio [aOR] = 14.91, 95% confidence interval [CI]: 12.09-18.39) and postnatal CMDs (aOR = 4.09, 95% CI: 2.72-6.15) compared with foreign-born mothers with low stress. The results of the subanalyses limited to black and Hispanic women separately were similar; high stress alone was associated with fourfold increased odds of CMDs among foreign-born Hispanic mothers (aOR = 4.27, 95% CI: 1.96-9.33). Conclusions: Findings suggest that identifying and alleviating high stress among pregnant women may reduce their risk of antenatal substance use and postnatal CMDs.