If every period is 45 days, it is normal and may be related to the level of estrogen secreted by the ovaries. Follicular growth cycle will lead to prolonged menstrual cycle, women’s ovulation is the next menstrual period about 14 days before ovulation, the due date will also be appropriate to extend backward, if a woman occasionally menstruation 45 days to come once, the rest of the time in 30 days or so to come once, is not normal, menstruation a week in advance or a week is delayed is in the normal range. When there are endocrine disorders, it is necessary to go to the hospital for examination and treatment, such as blood tests for sex hormone six levels, thyroid function tests, gynecological ultrasound, etc., and according to the different causes of the disease, take the appropriate medication to regulate.