Menstruation is a normal physiological process for women, and it usually occurs once every 28-30 days, with 5-7 days of advancement or postponement considered normal. Generally, menstruation is affected by the living environment, mood and work intensity. Therefore, under normal circumstances, you should maintain a happy mood, regular diet and regular life, which is conducive to regular menstruation. In general, if your period is delayed, you need to come to the hospital for an ultrasound and a sex hormone test to observe the thickness of the uterine lining and to find out the reason for your delayed menstruation. If menstruation is early, it is usually necessary to consider whether ovarian function is declining, and it is also necessary to do a sex hormone test to observe the fluctuation of sex hormones and understand the cause of early menstruation. In the reproductive department, a common cause of irregular menstruation is polycystic ovary syndrome (PCOS), which usually occurs once every 30-90 days, and the patient consults the doctor with irregular menstruation or delayed menstruation. At this time, it is necessary to observe whether the patient’s follicles on the ovaries are more than 12, and the sex hormones are higher in LH than in FSH, so that some pharmacological interventions can be done to make the patient’s menstruation regular.