Clinically, early menstruation may be caused by luteal insufficiency, inflammation of the endometrium, submucosal fibroids, and submucosal polyps. Postponed menstruation is often caused by polycystic ovary syndrome, premature ovarian failure, pelvic tuberculosis, endometrial tuberculosis, and complete adhesions of the uterine cavity after repeated abortions, resulting in clinical amenorrhea. For early or delayed menstruation, it is advisable to undergo clinical tests, such as blood tests for sex hormone 6 and thyroid function on the day after menstruation, to find out whether the ovaries are functioning normally and whether there is hyperprolactinemia and hyperandrogenemia. In addition, ultrasound will be done to check whether there are polycystic changes in the ovaries, pelvic tumors, endometrial polyps, etc.