Several screening procedures have been proposed to detect ovarian and endometrial cancer. However, none of them is sensitive and specific enough to be used in population-based screening programs. During our 5 year long study, 5013 asymptomatic women (44% premenopausal and 56% postmenopausal women) were scanned by transvaginal color and pulsed Doppler ultrasonography in an attempt to detect malignancy. These women had 404 adnexal cysts; 70 had resolved spontaneously on follow-up scans and 18 persisted. Another 316 sonographically benign cysts are still in the procedure of follow-up second scans. Of 5013 women, four women had stage I ovarian carcinoma and six had stage I endometrial carcinoma. There was one false-positive case encountered with an endometrioma. Only 14 women were subjected to major operative intervention; others underwent minor procedures based on the benign scan findings. No medical or surgical complications were reported. Transvaginal color Doppler ultrasonography, a noninvasive procedure, can detect ovarian and endometrial carcinoma in asymptomatic women and may be used as a screening procedure for these diseases.