If the patient has had a normal period after taking the emergency contraceptive pill, the second month of delayed menstruation is not related to the emergency contraceptive pill. If a patient has a regular period and has an occasional delay in menstruation, it may be related to emotional stress, increased work or study pressure, excessive weight loss or change in work or study environment. If the patient’s menstruation is delayed for more than 7 days, ultrasound can be done to observe the thickness of the endometrium and wait for the onset of menstruation according to the thickness of the endometrium or use western and Chinese medicines such as progesterone and pellets to promote the onset of menstruation. However, if the patient’s menstruation is delayed within 7 days, it is a normal fluctuation of menstrual cycle and can be treated without any examination or treatment.