Normally, progesterone is taken for 3-5 days in a row and then menstruation will occur after 3-7 days of discontinuation. If you do not have your period for more than 10 days after stopping the medication, you need to consider if you are pregnant or have other causes of menopause, such as pituitary, ovarian and endometrial lesions. Progesterone is a progestin and can be used to treat irregular periods and induce menstruation. If there is no pregnancy, withdrawal bleeding can normally occur about 3-7 days after stopping the medication after oral administration. If both estrogen and progesterone are insufficient, simply taking progesterone orally only may not necessarily lead to menstruation after stopping the medication. If you do not have menstruation for more than 10 days, you should promptly go to the hospital for review. Secondly, the number of days and the dosage of the medication will affect the time of menstruation, so it is recommended to take the medication under the guidance of a professional doctor, taking into account your own situation. Irregular menstruation is related to personal routine, emotions, mental stress and certain drugs taken. If it is occasionally delayed, it usually does not need treatment and can be regulated first.