The menstrual cycle is regulated by hormones. Luteinizing hormone and follicle-stimulating hormone, which are produced by the pituitary gland, promote ovulation and stimulate the ovaries to produce estrogen and progesterone.
Menstruation begins in inner wall of uterus as a result of very
low level of estrogen and progesterone.
Estrogen and progesterone are the female hormones secreted in
ovary. When sufficient quantity of estrogen and progesterone are
secreted wall of the uterus is repaired.
Lack of both estrogen and progesterone leads to menstruation.
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