Menstruation occurs after taking progesterone, mainly because it is related to changes in hormone levels in the body, indicating that the dose of progesterone is now in the body as well as accumulated to a certain level. The endometrium loses the support of progesterone, the endometrium undergoes ischemic necrosis, and the endometrium is shed, resulting in withdrawal bleeding, which leads to the onset of menstruation, which is the principle of menstruation. And progesterone not only has the effect of delaying menstruation will also play a role in making menstruation come early, while progesterone is also an important drug to protect the fetus, so must be taken under the guidance of a doctor to prevent unexpected effects. During the progesterone period, women need to take appropriate measures, do not eat cold and can stimulate the uterus food, pay attention to the uterus warmth, do not let the uterus cold, otherwise it will cause abdominal pain and other discomfort.