At the age of 47, each menstrual period is one week early. It is normal if the interval between two menstrual periods remains above 21 days, and abnormal if it is <21 days. Menstruation in healthy women is cyclical and self-limiting. Day 1 of bleeding is the beginning of the menstrual cycle, and the interval between two menstrual periods on day 1 is one menstrual cycle. The menstrual cycle fluctuates, not exactly once every 30 days, but from 21 to 35 days, once every 28 days on average, so it is a physiological phenomenon that the menstrual cycle occurs 1 week earlier, but not shorter than 21 days each time. Unless the menstrual cycle was shorter before, and now it is advanced by 1 week on the basis of the original menstrual cycle, and the menstrual cycle is less than 21 days after the advancement, it is abnormal, which may be related to the decline of the ovarian function, the follicle can not be developed and mature, and can not be normal ovulation. If the menstrual cycle is ≥21 days, the amount of menstruation is normal, and there is no other discomfort, observation and follow-up are sufficient; on the contrary, ultrasound and endocrine examination should be performed to rule out pathological factors.