This study examined the psychological impact of pre-term birth among adolescent mothers and how it compared to the psychological impact of pre-term birth among adult mothers and full-term birth among adolescent mothers. Fifty-two mothers completed a survey immediately prior to the discharge of their infants from hospital and approximately three months later. Contrary to our hypotheses, adult mothers of pre-term infants reported higher levels of psychological distress and threat appraisal pre-discharge than did adolescent mothers. Post-discharge this difference had dissipated. At the same time, there was no difference between the mothers in the reported helpfulness of social support, although all groups reported a decline in support from pre-to post-discharge. These findings help challenge prevailing assumptions about the transition to motherhood and have implications for service delivery and interventions.