When a woman is over 40 years old, she enters the perimenopausal period, when menopause is considered normal. So at the age of 40 some people will have irregular menstruation, manifested as early menstruation, prolonged menstruation time, some people will also have a prolonged cycle, that is, after 2-3 months to a period, are normal phenomena, can go to the hospital for examination, if there is no lesion, observation can be. However, if it is excessive menstruation and prolonged periods must be treated to avoid causing anemia and affecting health. Normal women in China, the average age of menopause is 48-52 years old.