If the patient usually has a regular period and occasionally a period is delayed for 15 days, there are two main possibilities to consider: first, pregnancy. For women who have a sexual life, when a period is delayed, the possibility of pregnancy must be considered first, and a blood or urine chorionic gonadotropin test is needed to determine this. Second, episodic delayed menstruation, because menstruation is susceptible to temporary disorders due to seasonal changes, weather changes, emotional changes, increased work and study stress, etc. Ultrasound is needed to observe the condition of the endometrium. If the thickness of the endometrium reaches 1.0cm, you can wait for the onset of menstruation; if it is around 0.8cm, you can use progesterone to promote the onset of menstruation; if the endometrium is thin, you can use estrogen and progestin to promote the onset of menstruation.