Teenage mothers may not "mature out" of substance use during young adulthood, and this non-normative trajectory of use may contribute to negative outcomes for teenage mothers and their offspring. Pregnant teenagers (age range=12-18 years; 68% Black) were recruited from a prenatal clinic and interviewed about their substance use, and subsequently re-interviewed six and ten years later (n=292). Consistent with the literature, early tobacco and marijuana use were risk factors for young adult use. Other substance use, peer adolescent use and mental health indicators were more important than race and socioeconomic status (SES) in determining which teenage mothers would use tobacco, engage in binge drinking, and use marijuana as young adults. However, race and SES were significant predictors of quitting tobacco use and marijuana use by the 10-year follow-up. Depression was associated with both persistent tobacco use and marijuana use in teenage mothers. These results illustrate the long-term consequences of teenage childbearing and identify modifiable risk factors for later health risks that should be addressed among younger mothers.