Changes

Menarche is the onset of menstruation in an adolescent.  This average age of menarche is twelve, but there is much variation.  Amenorrhea is an unusual absence of menstruation and should be cause for medical consultation.

Menarche is the onset of menstruation in an adolescent.  This average age of menarche is twelve, but there is much variation.  Amenorrhea is an unusual absence of menstruation and should be cause for medical consultation.

==Purpose of Menstruation==

==Differing Views on the Purpose of Menstruation Through History==

A number of hypotheses have been put forth regarding the purpose or benefit of menstruation:

A number of hypotheses have been put forth regarding the purpose or benefit of menstruation:

* The ancient physician [[Hippocrates]] held that menstruation was the body's means of purging itself of bad [[humor]]s, based on his belief that an excess of blood in the body led to health problems;

* The ancient physician [[Hippocrates]] held that menstruation was the body's means of purging itself of bad [[humor]]s, based on his belief that an excess of blood in the body led to health problems;