Heavy menstrual bleeding (HMB), previously known as menorrhagia or hypermenorrhea, is a menstrual period with excessively heavy flow. It is a type of abnormal uterine bleeding (AUB).
Abnormal uterine bleeding can be caused by structural abnormalities in the reproductive tract, anovulation, bleeding disorders, hormonal issues (such as hypothyroidism) or cancer of the reproductive tract. Initial evaluation aims at determining pregnancy status, menopausal status, and the source of bleeding. One definition is bleeding lasting more than 7 days or the loss of more than 80 mL of blood heavy flow.
Treatment depends on the cause, severity, and interference with quality of life. Initial treatment often involve birth control pills. Tranexamic acid, danazol, progesterone IUDs, and NSAIDs are also helpful. Surgery can be an effective for those whose symptoms are not well-controlled with other treatments. Approximately 53 in 1000 women are affected by AUB.
A normal menstrual cycle is 21–35 days in duration, with bleeding lasting an average of 5 days and total blood flow between 25 and 80 mL. Heavy menstrual bleeding is defined as total menstrual flow >80ml per cycle, soaking a pad/tampon at least every 2 hours, changing a pad/tampon in the middle of the night, or bleeding lasting for >7 days. Deviations in terms of frequency of menses, duration of menses, or volume of menses qualifies as abnormal uterine bleeding. Bleeding in between menses, outside reproductive age, or after sex is also abnormal uterine bleeding and thus requires further evaluation.
Usually, no causative abnormality can be identified and treatment is directed at the symptom, rather than a specific mechanism. However, there are known causes of abnormal uterine bleeding that need to be ruled out. Most common causes based on the nature of bleeding is listed below followed by the rare causes of bleeding (i.e. disorders of coagulation).
Excessive menses but normal cycle:
Painless:
Fibroids (leiomyoma) — fibroids in the wall of the uterus cause increased menstrual loss if they protrude into the central cavity and thereby increase endometrial surface area.