There are several reasons to consider brown leucorrhea: 1. there may be vaginal inflammation, you should check the routine leucorrhea to see which type of infection, check whether there is trichomonas, mycobacteria, bacteria or other mixed infections; 2. you can do gynecological internal examination to see whether there is inflammation of the cervix, or whether there are polyps in the cervix that cause brown leucorrhea; 3. do gynecological ultrasound to see the endometrial condition If the endometrium is overgrown or there are submucosal fibroids, it will cause brown leucorrhea; 4. It is also possible to be in the ovulation period, causing a small amount of vaginal bleeding and brown leucorrhea, which is physiological and lasts for about three days, observation is possible, no special treatment is needed.