Objective. The 2006 American Society for Colposcopy and Cervical Pathology consensus guidelines for management of abnormal cervical cytologic diagnosis made significant changes to referral recommendations for adolescent and pregnant populations. In this study, we sought to review the impact of these new guidelines on referral patterns, along with the incidence of cervical intraepithelial neoplasia 2/3 and cervical cancer in these 2 populations. Materials And Methods. After obtaining institutional review board approval, a retrospective chart review of 12,333 patients referred to a single colposcopy clinic between January 2004 and November 2009 was performed. This colposcopy clinic serves as a statewide referral center. All adolescent patients (<21 y) and pregnant patients were included for analysis. Patients were analyzed in 2 groups with respect to implementation of the 2006 guidelines. Statistical analysis was performed using χ and Student t test. Results. Between 2004 and 2007, before implementation of the 2006 guidelines, 9,346 patients were referred to the colposcopy clinic. Overall, 1,398 adolescents and 958 pregnant patients were identified and included in the analysis. The mean age was 23.0 years (range = 10-60 y). Of the 1,398 adolescent patients, atypical squamous cells of undetermined significance (ASCUS) Pap smears accounted for 406 referrals (29.0%). Of the 958 pregnant patients, ASCUS cytologic diagnosis accounted for 284 referrals (29.6%). One case of squamous cell carcinoma (SCC) was identified in the pregnant population (0.1%), and no cases of SCC were diagnosed in the adolescent population. After implementation of the 2006 guidelines, between 2008 and 2009, a total of 2,987 patients were referred, including 113 adolescent patients and 168 pregnant patients. Mean age was 25.5 (range = 16-54 y), which was not significantly different from 2004 to 2007, p = .79. Atypical squamous cells of undetermined significance accounted for 6 referrals (5.3%) in the adolescent population and 15 referrals (8.9%) in the pregnant population. The decrease in the proportion of ASCUS cytologic diagnosis referrals in these populations was statistically significant at p < .001. No adolescent or pregnant patients were diagnosed with SCC during their colposcopic evaluation. Conclusions. The 2006 American Society for Colposcopy and Cervical Pathology consensus guidelines decreased the number of ASCUS cytologic diagnosis referrals to colposcopy in the adolescent and pregnant populations. The overall number of patients with SCC in these populations is quite small, therefore practitioners can be reassured that the new screening guidelines are unlikely to miss this diagnosis. These guidelines provide an efficient, evidence-based approach to the cytologic evaluation of these special populations. Copyright © 2011 American Society for Colposcopy and Cervical Pathology.