Changes

'''Menstruation''' or menses occurs at the end of a [[placenta]]l [[mammal]]'s menstrual cycle. There are two types of menstruation:

'''Menstruation''' or '''menses''' occurs at the end of a [[placenta]]l [[mammal]]'s menstrual cycle. There are two types of menstruation:

* Overt menstruation, occuring in [[human]]s and [[great apes]], in which the lining of the [[uterus]] is shed and expelled from the body;

* Overt menstruation, occuring in [[human]]s and [[great apes]], in which the lining of the [[uterus]] is shed and expelled from the body;

* Covert menstruation, occuring in all other placental mammals, in which the [[endometrium]] is reabsorbed.

* Covert menstruation, occuring in all other placental mammals, in which the [[endometrium]] is reabsorbed.