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Menstrual flow

Menstrual flow

The menstrual cycle is the series of changes the body goes through to prepare for a pregnancy. About once a month, the uterus grows a new lining (endometrium) to get ready for a fertilized egg. When there is no fertilized egg to start a pregnancy, the uterus sheds its lining. This is the monthly menstrual bleeding (also called menstrual period) that happens from the early teen years until menopause, around age 50.

Current as of: February 11, 2021

Author: Healthwise Staff
Medical Review:
Sarah Marshall MD - Family Medicine
Martin J. Gabica MD - Family Medicine
Kathleen Romito MD - Family Medicine
Rebecca Sue Uranga MD - Obstetrics and Gynecology