Under normal circumstances, after the age of 35, ovarian function declines, menstruation will gradually decrease. However, there is a normal amount of decrease, not very little, is relative to the previous amount of menstruation, a little less than the normal amount of menstruation, is normal. The normal amount of menstruation is 30ml-50ml, and if the amount of menstruation becomes less and fluctuates within this range, it is normal and not a big problem. If the amount of menstrual flow is less than 30ml after the age of 35, that is to say, use less than 6 or 7 sanitary napkins for one menstrual period, this is considered as low menstrual flow, and you need to go to the hospital for endocrine testing to see if the ovarian function is declining, and whether the level of estrogen and progesterone secreted by the ovaries is low, so the amount of menstrual flow is getting lower and lower after the age of 35, which is not normal. If it can be controlled within 30ml-50ml, this is normal.