OBJECTIVES: Management of patients with atypical squamous cells of undetermined significance (ASCUS) remains controversial. We chose to repeat the Pap smear after four months. If ASCUS persisted in this second test, the patient was advised to undergo colposcopy. Our objective is to determine the clinical significance and the prediction of neoplasia among these patients through a colposcopic examination. METHODS: Of 29,827 patients who had a Pap smear, ASCUS were detected in 1387 (5%) and persisted in the repeat smear of 225 (16%). Colposcopy and an additional Pap smear were performed on 186 patients. RESULTS: Out of 186 colposcopic evaluations, 91 (49%) were normal and the patients had a negative Pap smear. Colposcopy was abnormal in 95/186 patients (51%) (Table 1). Histology of the directed biopsies revealed 38 (21%) low-grade squamous intraepithelial lesions (LSIL) and 17 (9%) high-grade squamous intraepithelial lesions (HSIL). Forty patients (21%) with normal biopsies had ASCUS for the third time in the Pap smear. CONCLUSIONS: Colposcopic evaluation after a repeated Pap smear with ASCUS is an appropriate cost-effective management. Finding 30% of LSIL or HSIL justifies this additional investigation.