The purpose of this retrospective, matched-case comparison study was to compare outcomes and cost-effectiveness of comprehensive, interdisciplinary teen-centered prenatal care clinics (Young Women's Clinic & Teen Pregnancy and Parenting Clinic) with "traditional" adult-centered obstetric services (University of Washington Medical Center & Group Health Cooperative) in a university medical center and a staff-model HMO. The sample (n = 106) included 27 index teens from Young Women's Clinic and matched cases from the other three clinics, matched on nine risk variables. Findings showed that teen-clinic clients missed fewer appointments (0.96 vs. 2.29, p < 0.05), were more likely to be enrolled in the supplemental Medicaid program First Steps (p < 0.001) and WIC (p < 0.01), were more likely to have vaginal deliveries (90% vs. 75%, p < 0.05) and higher birth weight infants (3330 vs. 3084 g, p < 0.05), and were more likely to attend 2-week (p < 0.001) and 6-week postpartum exams (p < 0.05). Postpartum data were missing for the majority of adult-clinic subjects; teen-clinic postpartum outcomes included high contraception rates (87.5%), breastfeeding (62%), school return postpartum (63%), and long-term follow-up. Costs were lower for teen clinics based on outcomes; cost savings related to preterm labor were similar.