This paper explores the potential importance of marriage and childbirth as determinants of school-leaving in sub-Saharan Africa and identifies some of the common underlying factors that contribute to premature school-leaving and early marriage and childbearing. We find that the risks of leaving school during adolescence for reasons other than childbirth or marriage far exceed the risks associated with these two demographic events. Consistent with overall trends of rising school enrollment and declines in early marriage and childbearing, we also find that the risks of leaving school during adolescence because of childbearing or marriage have declined relative to the past. Among the possible common causes underlying premature departure from school and early marriage and childbearing, our results suggest that delayed ages of school starting—a factor associated with being behind grade for age—could be a factor predisposing girls to a greater likelihood of both leaving school early and early marriage and childbearing. These findings have important policy implications. First, to the extent that demographic events such as early marriage and childbearing trump the school environment as a determinant of school exit during adolescence, our data indicate that early marriage rather than early childbirth is more likely to limit girls’ educational horizons, at least in the case of francophone Africa. This result suggests that the reproductive health community should see early marriage as a central area of concern for adolescent reproductive health. Second, our results suggest that “schoolgirl pregnancy” rarely accounts for more than a relatively small percent of girls who leave school. Third, policies that inform parents about the value of starting their children in school on time are likely to have beneficial effects both for grade attainment and for adolescent reproductive health regardless of school quality.