Menstruation comes when you take progesterone, but not when you do not take progesterone, which is considered to be caused by the lack of progesterone in the body. Estrogen in the body is to promote the growth of the endometrium, while progesterone causes the endometrium to metamorphose, which causes the endometrium to shed and form menstruation. If there is not enough progesterone in the body, the endometrium will continue to grow and cannot be shed regularly to produce menstruation. Progesterone is produced after ovulation and progesterone deficiency may be the result of ovulation disorder. Progesterone withdrawal therapy may be given to young women without fertility requirements or to young adolescents. In women of childbearing age or premenopausal women, short-acting contraceptive pills may be given to regulate menstruation.