Progesterone is sufficient to thicken the endometrium if taken orally for three days, so just take it for three days. The main purpose is to promote the thickening of the endometrium, after stopping the drug the endometrium loses the support of exogenous progesterone, and there will be withdrawal bleeding, and the vast majority of them will have vaginal bleeding 3-7 days after stopping the drug. Progesterone pills can cause dizziness for about an hour after taking them orally, so it is recommended to take them orally before going to bed. If a patient is allergic to progesterone, the drug should not be taken orally to induce menstruation. When taking progesterone orally, you should also be careful to take it at a fixed time each day for better results.