There are many reasons for a thin endometrium and low menstrual flow, most of which are caused by the absence of normal ovulation or the decline of ovarian function, resulting in low estrogen levels in the body, a condition that may affect fertility or affect the amount and color of menstruation. If repeated scraping or abortion may destroy the basal layer of the endometrium, leading to the formation of endometrial scars or even the formation of uterine adhesions, which may also cause low menstrual flow and have to be restored through surgery. Some inflammatory diseases, such as common endometritis or pelvic tuberculosis, may invade the endometrium, affecting the growth of the endometrium and leading to congestion and edema of the endometrium, so the conditions that cause scanty menstruation must be dealt with according to the different causes.