BackgroundThe prevalence of alcohol use among pregnant women aged 18–44 years old increased in recent years. The influence of mental health issues on an individual’s likelihood to use alcohol during pregnancy has not been thoroughly investigated. This study will examine the association between experiencing a major depressive episode (MDE) in the past year and past-month alcohol use among pregnant women using the 2011–2020 National Survey on Drug Use and Health (NSDUH).MethodsPregnant women between the ages of 18 and 44 years old were included in the study for analysis. Multivariable logistic regression analysis was used to examine the association between past-year MDE and past-month alcohol use adjusting for age, race/ethnicity, marital status, and employment status. Additional logistic regression analysis was performed to investigate whether this relationship differed by trimester of pregnancy.ResultsA total of 6745 participants were included in the analytic sample. The prevalence of past-year MDE and past-month alcohol use was 7.67% and 9.15% respectively. Logistic regression analysis showed past-year MDE was significantly associated with past-month alcohol use in pregnant women adjusting for age, race/ethnicity, marital status, and employment status (aOR = 1.96; 95% CI, 1.34–2.87). This relationship became stronger in second and third trimesters of pregnancy.ConclusionsThis study showed a positive association between MDE and past-month alcohol use among pregnant women, with strongest effect estimates in the third trimester. These findings may inform approaches for improved screening guidelines and health education for individuals who may be at higher risk of prenatal alcohol use.