The main factors that affect the onset of menstruation in women come from the ovaries and the uterus. The main reasons why menstruation does not come on time when it should include: a. Patients stay up late for a long time, emotional problems, excessive dieting, stress, environmental changes and other adverse factors, resulting in disruption of the endocrine function of the ovaries. Second, women who have normal sexual life do not have good contraceptive measures, or the failure of contraceptive measures leads to pregnancy. Third, multiple abortions or intrauterine surgical operations, resulting in endometrial damage and uterine adhesions. IV. Suffering from endometrial tuberculosis causing absence of menstruation. V. Secondary amenorrhea caused by hyperprolactinemia, or Silhan’s syndrome, etc. Sixth, abnormal thyroid function or severe anemia.