Leviticus 12: Laws of Motherhood

Leviticus 12 says that a woman will be unclean for 7 days after she gives birth to a male child and for 2 weeks if she gives birth to a female child. The book further says that she would be unclean just like in her days of menstruation.
I think i should see that when exactly human world became aware of clinical causes of menstruation.

The chapter is important one!