Brown discharge at 12 weeks of pregnancy often may be a bleeding condition, usually caused by low placental position, pre-eclampsia, trichomonas vaginitis, cervicitis, cervical erosion, cervical polyps, cervical cancer, etc. Pregnant women should go to the hospital in time to check the routine leucorrhea and ultrasound, and according to the examination results, treat the cause. 1. low placental position: it is easy to have repeated painless bleeding, which can be manifested as brown vaginal discharge It can be manifested as brown vaginal discharge. In this case, pregnant women should pay attention to not having intercourse, not lifting heavy objects, resting in bed and avoiding strenuous activities. The vaginal bleeding should be treated promptly, and in case of heavy bleeding, miscarriage may occur. Under normal circumstances, pregnant women need to review the ultrasound once in 2 weeks. If the placenta position can grow upward, it will return to the normal placenta position after about 2-3 months; 2. Pre-eclampsia abortion: it is manifested as a small amount of vaginal bleeding or with lower abdominal discomfort, and pregnant women can have brown discharge from the vagina. If the fetus is developing normally, she can undergo fetal preservation treatment under the guidance of a doctor, such as taking oral dydrogesterone tablets, paying attention to bed rest and reducing activities. 3. Trichomoniasis: Patients may have vaginal mucous membrane congestion, and in severe cases, there are scattered bleeding spots and brown discharge from the vagina. In this case, you should go to the hospital for routine leucorrhoea examination and use symptomatic medication as prescribed by the doctor after clarifying the cause. You can clean your vulva with warm water, change your underwear regularly, keep your perineum clean and dry, and don’t eat spicy and stimulating food. 4. Cervicitis: It is manifested by increased vaginal discharge, yellowish, brown or pus-like, accompanied by vulvar itching or discomfort. This condition should be actively treated under the guidance of a doctor, but pay attention to early treatment, the cure rate is higher, while do not blindly take medication; 5, cervical erosion: manifested as vaginal discharge sometimes with blood, and then may appear brown discharge. If the examination reveals cervical erosion but there are no uncomfortable symptoms, there is no need for medication in this case. This is due to the increase in estrogen and progesterone content after pregnancy, which leads to ectopic columnar epithelium and thus causes the appearance of erosion, which is actually a physiological state. You can wash your vulva with warm water every night, pay attention to keeping your vulva clean and dry, and use cotton underwear to keep your vulva breathable. If there is an increase in leucorrhea, you can use localized vaginal pessary treatment under the guidance of your doctor; 6. Cervical polyps: some pregnant women have yellow or brown vaginal discharge with odor, or vaginal discharge with blood. At 12 weeks of pregnancy when the placenta is firm, surgical removal of polyps can be considered. If the pregnant woman has no discomfort and no vaginal redness, i.e. the polyp does not cause bleeding, it can be left untreated for a while and treated by surgery or conservative observation after the uterus returns to normal after 1 month postpartum; 7. Cervical cancer: it shows irregular vaginal bleeding and may appear as brown discharge. It is recommended to terminate the pregnancy if necessary and perform cervical conization, total hysterectomy, modified radical hysterectomy or radical hysterectomy for treatment, and choose chemotherapy, radiotherapy, targeted therapy and other adjuvant therapies after surgery according to the situation.