20-01: Abnormal Uterine Bleeding in Women of Reproductive Age

ESSENTIALS OF DIAGNOSIS

GENERAL CONSIDERATIONS

Normal menstrual frequency varies from 24 to 38 days with bleeding lasting an average of 5 days (range, 2–8 days) and a mean blood loss of 40 mL per cycle. AUB refers to menstrual bleeding of abnormal quantity, duration, or schedule. The International Federation of Gynecology and Obstetrics (FIGO) introduced the classification system for AUB in 2011, which was then endorsed by the American College of Obstetrics and Gynecology. This classification system pairs AUB with descriptive terms denoting the bleeding pattern (ie, heavy, light and menstrual, intermenstrual) and etiology (the acronym PALM-COEIN standing for Polyp, Adenomyosis, Leiomyoma, Malignancy and hyperplasia, Coagulopathy, Ovulatory dysfunction, Endometrial, Iatrogenic, and Not yet classified) (eTable 20–1). In adolescents, AUB often occurs because of persistent anovulation due to the immaturity of the hypothalamic-pituitary-ovarian axis. Once regular menses have been established during adolescence, ovulatory dysfunction AUB (AUB-O) accounts for most cases. AUB in women aged 19–39 years is often a result of pregnancy, structural lesions, anovulatory cycles, use of hormonal contraception, or endometrial hyperplasia.

CLINICAL FINDINGS

A. Symptoms and Signs

The diagnosis depends on the following: (1) confirming uterine source of the bleeding; (2) excluding pregnancy and confirming patient is premenopausal; (3) ascertaining whether the bleeding pattern suggests regular ovulatory bleeding or anovulatory bleeding; (4) determining contribution of structural abnormalities (PALM), including risk for malignancy/hyperplasia; (5) identifying risk of medical conditions that may impact bleeding (eg, inherited bleeding disorders, endocrine disease, risk of ...