“Abnormal” Uterine Bleeding Is Common During the Menopausal Transition

So-called abnormal uterine bleeding is common in women of late reproductive age, but which bleeding patterns should be considered normal and which are distinctly abnormal? Investigators analyzed 10 years of menstrual diaries from 1320 black, white, Chinese, and Japanese participants in the Study of Women's Health Across the Nation (SWAN; age range at enrollment, 42–52).

Menses ranged in duration from 1 to 132 days (mean, 5.9 days), and 431 women experienced their final menstrual period during the study. Cumulative percentages of women with at least one, two, or three occurrences of bleeding episodes ≥10 days in length were 91.0%, 87.5%, and 77.7%, respectively. Two thirds of women had at least three occurrences of ≥6 days of spotting; one th…