Question

when and how does menstruation occur​

Answer 1

Explanation:

Menstruation occurs in cycles. The ovaries prepare an egg (oocyte) for release and the womb (uterus) prepares a lining to nourish the egg if it is fertilised.

When the egg is not fertilised, the lining of the womb is shed and a woman gets her period (menstrual bleeding).

Hope it helps...