Objective: To assess the perinatal outcomes of a subsequent pregnancy among adolescent mothers living in Peru. Methods: A large hospital-based retrospective cohort study was conducted to evaluate singleton births during a 9-year period (2001-2009). The study population was divided into 3 groups: adolescents aged 15-19 years who had 1 previous parturition (n = 2074), nulliparous adolescents (n = 20 721), and multiparous adults aged 20-29 years (n = 23 129). Results: No significant differences were found between multiparous adolescents and the 2 control groups with regard to preterm delivery, perinatal death, and 5-minute Apgar score below 7. Logistic regression analysis showed no significant differences in the rates of cesarean delivery or preterm birth before 34 or 37 weeks. After adjusting for confounding factors, low birth weight (LBW) and small for gestational age (SGA) were more likely to occur during a subsequent pregnancy among adolescent mothers than during the 1st pregnancy among nulliparous adolescents. The odds ratios were 1.38 (95% CI, 1.14-1.67) and 1.27 (95% CI, 1.02-1.56), respectively. Conclusion: Multiparous adolescents are more likely to experience LBW or SGA than are nulliparous adolescents. No significant differences in other perinatal outcomes were found among the 3 study groups. © 2011 International Federation of Gynecology and Obstetrics.