In order to evaluate the etiology, incidence of malignancy, clinical risk factors and the interval between menopause and the onset of abnormal vaginal bleeding in postmenopausal women, 381 cases with a complete medical history and available histologic findings were enrolled in this study at the National Taiwan University Hospital from 1989 to 1991. The results showed that 212 (55.6%) of these women had normal histologic findings and 83 (21.9%) had benign pathologic findings, whereas 14 (3.6%) had cervical intraepithelial neoplasia (CIN), 42 (11%) had endometrial hyperplasia, 19 (5%) had cervical cancer and 11 (2.9%) had endometrial cancer. Twenty-nine (7.6%) of the cases suffered from either CIN III or cervical cancer; this number was twice as high as those with endometrial atypical hyperplasia and endometrial cancer (n = 13, 3.4%). In addition, various risk factors, especially obesity, were found to be significantly correlated with malignancy. Fractional curettage should be performed for postmenopausal bleeding patients to ensure accurate diagnosis and correct management.