The prevalence of cervical intraepithelial neoplasia in young women is increasing worldwide. Frequency of the abnormal Papanicolau smears was examined in sexually active young females aged 13 to 19 years. The smears were reported as within normal limits or with benign cellular changes due to inflammation in 96.2% of cases. The cytological changes were related in 2.5% of cases of HPV infection, in 1.0% of cases to CIN I and in 0.3% of cases to CIN II. These results show a frequency of 3.8% of abnormal smears.