We evaluated 14,317 asymptomatic or minimally symptomatic women for ovarian carcinoma with transvaginal color Doppler ultrasound. The resistance index was calculated for at least five separate cardiac cycles in each case, and the mean was calculated. We discovered 624 benign adnexal masses: in every case except one the resistance index was greater than 0.40. There were 56 malignant adnexal masses, 16 of which were stage I ovarian cancers. Neovascularization was found in six of the seven stage I primary neoplasms and in all of the nine stage I secondary ovarian cancers. In all, the RI was less than or equal to 0.40. There were 40 advanced ovarian cancers revealed (stage III or IV); 39 showed abnormal color-flow pattern with the resistance index less than 0.04.