Estimates from the National Longitudinal Survey of Youth (1979-1987) indicate that differences in high school completion rates between women who have a teenage birth and those who do not are affected by the birth itself, family background characteristics and individual heterogeneity. Merely having a teenage birth leads to a 50% reduction in the likelihood of high school completion, compared with not having a teenage birth. Individual heterogeneity accounts for a 42% reduction in the likelihood of finishing high school among those who have a birth before age 17, and a 30% reduction among those who have a birth between ages 17 and 19, compared with those who do not have a teenage birth. However, individual heterogeneity accounts for less than 30% of the difference in the likelihood that black teenage mothers will complete school, compared with more than 50% among Hispanics and whites. Family background variables, such as maternal education and parental marital stability, also have positive effects on school completion.