The causes of non-menstruation are the following: 1. diseases, mainly including wasting diseases, such as severe tuberculosis, severe anemia, malnutrition, etc.; specific endocrine diseases, such as obesity reproductive incompetence malnutrition disease, etc.; the influence of some endocrine disorders in the body, such as adrenal, thyroid, pancreatic and other dysfunctions. 2. atresia of the lower part of the reproductive tract, such as the cervix, vagina, hymen, labia, etc., with A part of congenital atresia, or acquired injury causing adhesive atresia, although there is menstruation, but the menstrual blood can not flow out, this situation is called occult or pseudo-amenorrhea. 3, reproductive organs are not sound or stunted. Some congenital absence of ovaries, or ovarian dysplasia, can not produce estrogen and progesterone, so the endometrium can not undergo cyclic changes, and there will be no endometrial shedding, so also can not menstruate. There is also congenital absence of the uterus, or endometrial dysplasia, endometrial damage, even if the ovaries are functional and the secretion of estrogen and progesterone is normal, there will be no menstruation. 4. Tuberculous endometritis. The endometrium is inflamed and damaged to varying degrees due to the invasion of tuberculosis bacteria into the endometrium, resulting in scar tissue and amenorrhea. 5. Abnormal function of the pituitary gland or hypothalamus. The pituitary gland secretes gonadotropin, which has the role of regulating ovarian function and maintaining menstruation. If the pituitary gland is dysfunctional, it will affect the secretion of gonadotropins, which in turn will affect the function of the ovaries, and abnormal ovarian function will cause amenorrhea. In addition, hypothalamic dysfunction can also cause amenorrhea. There are many causes of hypothalamic dysfunction, such as mental stimulation, excessive sadness, fear and anxiety, stress and exertion, as well as environmental changes and cold stimulation, etc. Amenorrhea caused by the hypothalamus is relatively common.