Taking progesterone will not reduce the amount of menstruation, it may increase the amount of menstruation. If the menstruation is delayed for more than 7 days, during which there is sexual life without good contraception, and the amount of menstruation is less after taking progesterone capsules for 5-10 days in a row, it is normal to consider that there is no real menstruation and to exclude unintended pregnancy. Because bleeding is not necessarily menstruation, consider abnormal bleeding due to pregnancy or ectopic pregnancy, go to the hospital in time to do ultrasound examination to see the situation of the uterine adnexa, blood test HCG and exclude unwanted pregnancy, if the thickness of the endometrium is thicker, consider it is not really menstruation, you can wait for 7-10 days again, the role of progesterone is to increase the body’s progesterone, so that the endometrium completely shed, bleeding. If it is an unwanted pregnancy, menstruation cannot come normally. Progesterone is a kind of fetus preservation drug for pregnant people, which promotes the endometrial lining to peel off to form retreating bleeding and has a protective effect on the endometrium.