Early pregnancy, pregnant women have brown vaginal discharge, may be a normal phenomenon, may also be the first sign of miscarriage, vaginitis or ectopic pregnancy and other causes, as follows: 1. Normal phenomenon: If a pregnant woman is in early pregnancy, after the embryo has been implanted, it will cause mild bleeding, manifested as brown discharge, which is a normal phenomenon. 2. Pre-eclampsia: It may be caused by excessive coitus or strenuous exercise during pregnancy, which stimulates the uterus and cervix and other parts of the uterus and cervix, which will lead to pre-eclampsia, and there will be vaginal bleeding or brown discharge and other symptoms, you should go to the hospital in a timely manner to check the ultrasound and progesterone, etc., to observe the condition of the embryo. 3. Vaginitis: it may be due to the low immunity during pregnancy, not pay attention to hygiene will make the virus and bacteria invade the vagina to produce inflammation, after the inflammation infection will cause the vagina to appear brown discharge, also accompanied by abdominal pain or abdominal distension and other symptoms. 4. Ectopic pregnancy: refers to the process of development of the egg in the uterus outside the bed, resulting in more brown discharge, will make the embryo death or severe pain and other symptoms, you should go to the hospital in a timely manner to confirm the diagnosis should be promptly terminate the pregnancy. If the symptoms of brown discharge in early pregnancy are serious, and the symptoms continue to not improve, you should promptly go to the hospital for treatment.