Objective: We have aimed at investigating the correlation between uterine artery flow waves and endometrial thickness as well as histopathologic changes in women who presented with either peri or postmenopausal bleeding as transvaginal ultrasonography is obviously less invasive than curettage; the low rate of morbidity or even mortality that exists for curettage is a disadvantage. Methods: We performed Doppler studies of the uterine artery in 78 women with postmenopausal and perimenopausal bleeding. In all of the patients diagnostic curettage was performed 1 to 7 days after ultrasonography. The curettage material obtained was examined at the Pathology Department of our hospital for histopathologic diagnosis. The specificity and sensitivity of the endometrial thickness and uterine artery resistance index (Rl) were evaluated to diagnose the malignant changes of the endometrium. Results: Fifty-seven women had non-malignant changes and 21 women had malignant changes on histologic examination of the endometrium. Uterine fibroids were detected in 18 women. When malignant changes were detected in the endometrium, uterine artery resistance index was always below 0.80. The mean uterine artery resistance index was significantly lower in the group of women with pathologic changes of the endometrium (Rl=0.706±0.085) compared to the group with non-pathologic changes (0.821±0.072) (p