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How much blood is typically lost during a menstrual period?
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menstruation
Cyclical changes during a woman's normal ovulatory menstrual cycle.
During a typical menstrual period, the total blood loss does not ordinarily exceed 50 milliliters (approximately 1.69 U.S. fluid ounces).1
The menstrual discharge consists of the disintegrating endometrium shed from the uterus, along with blood. This discharge remains fluid because the endometrium contains plasmin, an enzyme that dissolves blood clots. While this is the standard range, an abnormally profuse menstrual flow is medically referred to as menorrhagia.12