Study Objective: To evaluate regression rates among adolescents (aged <= 21) with cervical intraepithelial neoplasia (CIN) 2 managed expectantly and to determine factors associated with disease regression. Design: Cohort study using a colposcopic database of 2,996 women seen between August 1999 and November 2005. Setting: Colposcopy clinic in urban, tertiary care medical center. Participants: Adolescents with CIN 2. Routine management consisted of two options: immediate treatment or repeat colposcopic evaluation in 6 months. Main Outcome Measures: For those managed conservatively, regression was defined either as a subsequent normal colposcopy and/or biopsy and at least 2 smears read as negative for epithelial abnormality or at least 3 consecutive negative smears if repeat colposcopy was not performed. Demographic information, including age, was assessed to determine possible associations with disease regression. Results: Of the 93 adolescents, 53 (57%) elected to undergo immediate treatment with a diagnostic excisional procedure, and 40 (43%) chose management with colposcopic follow-up. Of those treated, high-grade disease (CIN 2+) was found in 40 (75%). Of the 36 young women followed conservatively (4 were lost to follow-up), regression after a median follow-up time of 378 days was documented in 14 (39%). Of the 22 adolescents not fulfilling our criteria for regression, only 3 had evidence of CIN 2 or worse during follow-up. The remaining 19 had either CIN 1 or mildly abnormal cytologic results. Kaplan-Meier survival estimates indicated younger age (<= 16 years) tended to be associated with decreased time to regression. Conclusion: Based on significant regression of CIN 2 among adolescent women, primary management in this population should consist of cytologic and colposcopic follow-up.