There is a little brown discharge in advance of menstruation and no more at this time to consider abnormal uterine bleeding, mostly related to ovulation bleeding, endocrine disorders, polyps, malignant lesions, pregnancy-related diseases, and so on. 1. Ovulation bleeding: if the bleeding occurs in the next menstrual period about 14 days before the onset of menstruation, be alert to the occurrence of ovulation bleeding, this bleeding is considered to be related to the endometrial irregularity caused by the decline in the level of oestrogen after ovulation, generally 2-3 days can be self-sustaining. 2. Endocrine disorders: If a woman is under stress, stays up late or has gynecological endocrine diseases such as polycystic ovary syndrome or premature ovarian failure, the follicles in the ovaries will grow and develop abnormally and be discharged due to endocrine disorders, which will lead to disorders of estrogen and progesterone, and irregular stripping of the endometrium, resulting in irregular vaginal bleeding. 3. Polyps: for women with endometrial polyps or cervical polyps, patients with irregular vaginal bleeding, prolonged menstrual period as the main clinical manifestations. 4. Malignant lesions: for patients with malignant lesions such as cervical cancer and endometrial cancer, due to the rapid growth of cancer cells, the lack of blood supply to the local tissues will cause tissue necrosis and a small amount of vaginal bleeding. 5. Pregnancy-related diseases: for women in reproductive age with normal sex life, if irregular vaginal bleeding occurs, first of all, we should exclude the occurrence of adverse pregnancy such as pre-menstrual abortion, ectopic pregnancy and so on. For women who have a little brown discharge in advance of menstruation and no more, it is recommended that they go to the gynecology department of a regular hospital, complete the relevant examinations, identify the cause of the disease, and treat it under the guidance of the doctor.