What is menstruation?

Really? your going to ask this?? well okay

Menstruation, or period, is normal vaginal bleeding that occurs as part of a woman's monthly cycle. Every month, your body prepares for pregnancy. If no pregnancy occurs, the uterus, or womb, sheds its lining.

Explanation:

it is the monthly breakdown of the walls of the endometrium of the uterus accompanied with blood known as mensis.

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