Clinical Question: Is the definition of menorrhagia as 80 mL or more of blood loss during menstruation clinically meaningful?

Setting: Population-based

Study Design: Cross-sectional

Synopsis: In this study, menstrual volumes of less than 80 mL were compared with volumes of 80 mL or more to assess associations with clinically meaningful outcomes. This cutoff often has been used in research studies, and the authors wanted to evaluate its validity. The study included 226 British women with complaints of heavy menses who answered questionnaires and whose blood loss was measured. The women were grouped into four categories according to the following menstrual blood volumes: less than 50 mL, 50 to 79 mL, 80 to 119 mL, and 120 mL or more (n = 104, 45, 35, and 42, respectively).

The groups of 50 to 79 mL and 80 to 119 mL did not differ in terms of dysmenorrhea, problems with containment, feeling unwell/tired, poor iron status, or hysterectomy within the next eight months. Some trend associations with menstrual volume were evident for several of these outcomes because of the influence of the groups at the extremes of menstrual blood volume. Variables related to pain with periods were associated inversely with menstrual volume in this group of women.

Bottom Line: The definition of menorrhagia as more than 80 mL of blood loss should not be used because it does not predict clinically meaningful outcomes. (Level of Evidence: 2c)