Objective: To evaluate the duration of high-risk HPV-associated cancer risk. Study design: Patients who had had a routine diagnostic Hybrid Capture Tube Test (HCT) due to squamous cell abnormalities of the uterine cervix were followed-up until the endpoint of histologically diagnosed cervical intraepithelial neoplasia (CIN). Results: Six hundred and thirty-eight women were followed during a cumulative follow-up of 16,423 patient months. The adjusted relative risk associated with the positive HR-HCT test for high-grade CIN/52.0 (20.9- 19.2)/ proved to be higher than that of the cytological atypia/5.44 (2.52- 11.77)- /. At the end of the 30 months of follow- up the crude and adjusted risks for CIN2+ were 214.3 (28.4- 1615.7) and 196.7 (25.4- 1525.2), respectively in the HPV 16/18 group, and after 30 months, the crude and adjusted RR decreased to 57.6 (10.4- 318.9) and 29.2 (5.02- 170.0). In the groups of other high- risk types and possibly high-risk types the general tendency was the same. However, new CIN2+ cases were not detected after the 30th month of follow-up in these later groups. Conclusions: HPV16/18 associated relative risk is nearly 200 times higher than that of the HPV negative population and an outstanding risk persists with duration of about 30 months. The risk is manifested in progression to high-grade CIN lesions mainly within a 2 years interval after the first detection of HPV 16/18 infection. Objective: To evaluate the duration of high-risk HPV-associated cancer risk. Study design: Patients who had had a routine diagnostic Hybrid Capture Tube Test (HCT) due to squamous cell abnormalities of the uterine cervix were followed-up until the endpoint of The histologically diagnosed cervical intraepithelial neoplasia (CIN). Results: Six hundred and thirty-eight women were followed during a cumulative follow-up of 16,423 patient months. The adjusted relative risk associated with the positive HR-HCT test for high-grade CIN / 52.0 (20.9- 19.2) / proved to be higher than that of the cytological atypia / 5.44 (2.52- 11.77) - /. At the end of the 30 months of follow-up the crude and adjusted risks for CIN2 + were 214.3 (28.4- 1615.7 ) and 196.7 (25.4-1525.2), respectively, in the HPV 16/18 group, and after 30 months, the crude and adjusted RR decreased to 57.6 (10.4-318.9) and 29.2 (5.02-170.0). In the groups of other high - risk types and possibly high-risk types the general tendency was the sam e. However, new CIN2 + cases were not detected after the 30th month of follow-up in these later groups. Conclusions: HPV16 / 18 associated relative risk is nearly 200 times higher than that of the HPV negative population and an outstanding risk persists with duration of about 30 months. The risk is manifested in progression to high-grade CIN lesions mainly within a 2 years interval after the first detection of HPV 16/18 infection.