Menstruation is the shedding of the uterine lining. It usually lasts 3-7 days and marks the start of the menstrual cycle. Hormonal changes lead to the release of the lining if no pregnancy occurs, resulting in menstrual bleeding.
Menstruation is the shedding of the uterine lining. It usually lasts 3-7 days and marks the start of the menstrual cycle. Hormonal changes lead to the release of the lining if no pregnancy occurs, resulting in menstrual bleeding.