Thirty-seven patients who underwent cone biopsy for cervical intraepithelial neoplasia (CIN) of varying gravity have been considered. The follow-up points to the therapeutic as well as diagnostic value of this intervention (92% success). Analysis of the responses provided by colpocytology in comparison with those provided by biopsy, evidences the poor diagnostic reliability of the pap-test with respect to intraepithelial lesions of the uterine cervix (under-estimated in 51% of cases compared to biopsy). Operation did not substantially modify patients' reproductive capability (5 pregnancies of which 3 developing, during the control period) an extremely important factor in view of the young age of patients (average 31 years).