Why Do Women Menstruate?

Virtually all female mammals tend to leak at least a little bit of blood when they come into season (are fertile for mating).  But humans go into overload in terms of quantity.  No other mammal can compare.


It may be a visual thing.  Because humans have a relatively poor sense of smell, the sight of the blood on a female may have been an important signal to our primitive ancestors that a woman was fertile (inbetween bouts of pregnancy and extended breastfeeding, which often inhibits fertility).  So women who shed the most blood, became most attractive to males.


Or it may have been a coincidence.  Females who shed a lot of blood evidently are well-nourished themlselves, and have enough blood extra to nourish a developing baby; so these were the same females who were most likely to successfully bear a child, and thus pass their genes onto the next generation.

It goes all the way back to Adam and Eve. Since Eve disobeyed God, he cursed her with the burden of labor pains, cramps, and bleeding. The purpose of menstruation is to remove the old ovaries out of the body, so the body could make room for the new ovaries.

To put out the chemical in our body!