menstruation
Not to be confused with defloration
Menstruation is the shedding of the uterine lining (endometrium). It occurs on a regular basis in reproductive-age females of certain mammal species. Overt menstruation (where there is bleeding from the uterus through the vagina) is found primarily in humans and close evolutionary relatives such as chimpanzees.
See also
The following tags implicate this tag: menstrual_cramps (learn more).
