We report about 142 patients from whom colposcopically directed cervical punch biopsies were taken which showed condylomatous lesions with or without cervical intraepithelial neoplasia (CIN). Fifty-six (39.4%) of these women used oral contraceptives (OC) for at least two years before examination. We used DNA in situ hybridization on all biopsies for detection of human papillomavirus (HPV)-DNA. Among OC users a significant trend towards higher HPV infection rates in high grade CIN (odds ratio 2.9, P less than 0.05) was found, whereas non-users of oral contraceptives had the highest HPV infection rate in condylomatous lesions without CIN (odds ratio 0.5, P less than 0.05). Thus in OC users HPV infection was about 24 times more likely in CIN III as in condyloma, while among non-users the trend was the other way round (7-fold likelihood of HPV positivity in condyloma compared to CIN III). Other known risk factors for cervical carcinoma did not influence HPV infection rates in either group.