Low menstrual flow means that the menstrual cycle is basically normal and the amount of menstruation is significantly reduced or even spotted, or the period is shortened by less than two days and the amount of menstruation is also low. There are many clinical reasons for reduced menstrual flow, such as thin endometrium, uterine adhesions, low thyroid function, etc. Whether low menstrual flow will affect pregnancy can be analyzed as follows: 1. Low menstrual flow but normal ovarian function generally does not affect pregnancy. The normal range of women’s menstruation is large, about between 80-100 ml. Some women’s menstruation belongs to the normal range of low, while their ovarian ovulation function and secretion of female hormone function are within the normal range, which can conceive normally; 2. Non-reproductive system and endocrine caused by low menstrual flow, there is a certain probability of fertility. If the low menstrual flow is due to systemic wasting diseases, such as tuberculosis, malnutrition, anemia, etc., or mental factors such as stress, depression, fear, and other factors such as exertion and environmental changes, it is also possible to conceive. If the low menstrual flow is due to diseases such as endocrine hypofunction, tumors, or uterine hypoplasia, the chances of infertility are greatly increased. Therefore, for functional reduced menstrual flow, the first step is to look for the causative factor and provide targeted treatment. If no abnormality is found after examination, there is no need to be overly nervous. The incidence of infertility in women with low menstrual flow is no different from that of women with normal menstrual flow, so special treatment is generally not necessary.