Pregnancy among unmarried adolescents has been linked to negative personal control beliefs. In contrast, self-agency beliefs about control over future possibilities have been linked to delay in subsequent childbearing. In this secondary analysis, we examined factors associated with self-agency change in 429 unmarried adolescent mothers from intervention and control groups of a nurse home visitation study. Adolescent mothers who participated in a sustained relationship with a nurse made greater gains in self-agency than did control group mothers (p = .034). Adolescents with lower cognitive ability who were behind their age-appropriate grade level in school made the greatest self-agency gains.