Senior girl’s menstruation does not go refers to prolonged periods, which may be caused by endocrine disorders, hypothalamic-pituitary-ovarian gonadal axis dysfunction, endometritis and other reasons. 1. Endocrine disorders: may be caused by over-nutrition, psychological stress, environmental pollution and other reasons. Abnormal secretion of sex hormones and no ovulation may occur, thus symptoms such as low menstrual flow and prolonged menstrual period may occur. 2. Hypothalamic-pituitary-ovarian gonadal axis dysfunction: the dysfunction may be caused by trauma, infection, mental stress, etc., which triggers irregular shedding or delayed repair of the endometrium, which may lead to prolonged menstruation. 3. Endometritis: it means that bacteria break through the defense of the cervix and invade the endometrium and inflammation occurs. Due to the stimulation of inflammation, patients may have increased menstrual flow and prolonged menstrual period. It may also be caused by other reasons, it is recommended that senior girls who do not go menstruation go to the hospital in time, and follow the doctor’s instructions for treatment, to avoid delaying the condition.