Research on prenatal depression is relatively sparse despite its demonstrated importance in predicting mother and child outcomes. We tested the degree to which childhood trauma predicted prenatal depressive symptoms and whether this relation was moderated by social support as well as risk status of the mother in 682 pregnant adults and teens. Results indicated that childhood trauma significantly predicted prenatal depressive symptoms; the moderating effect between social support and child trauma was marginally significant when models were constrained to be equal across group. Using multigroup moderation analyses, however, moderation effects were significant for teens but not adults. Findings expand the current knowledge on prenatal depression and have implications for prevention/intervention programs, particularly for pregnant adolescents.