There are many reasons for brown blood a few days before the menstrual period, generally considered to be related to luteal function, but may also be related to ectopic pregnancy or pre-eclampsia. The most common cause of brown bleeding a few days before menstruation is luteal insufficiency, and the patient needs to observe whether the above-mentioned condition will occur again next month. If so, you can visit the hospital on the 17th-20th day of your period to check your endocrine hormones and see if your progesterone is low. If it is low, you will need to take progesterone supplementation. In addition, if the patient has a history of menopause and has abdominal pain when she has brown blood, she should consider the possibility of ectopic pregnancy or pre-eclampsia, and it is recommended to go to the gynecology department of the hospital for ultrasound and blood HCG examination to make a clear diagnosis and early treatment. After excluding the above-mentioned cases, the manifestation of brown blood may also be caused by cervical diseases, such as cervical polyps, cervical precancerous lesions, cervical cancer, etc. In conclusion, once a patient has brown blood before menstruation, it is recommended to seek medical treatment in time.