Brown discharge in 3 weeks of pregnancy may be related to bleeding from fertilized egg implantation, preeclampsia, ectopic pregnancy or gynecological diseases. 1. Fertilized egg implantation bleeding. Early pregnancy brown discharge is likely to be fertilized egg implantation to stimulate the endometrium small blood vessel rupture caused by a small amount of bleeding, usually brown discharge, accompanied by mild abdominal pain symptoms, usually lasts about 2 to 3 days to disappear. 2. Pre-eclampsia. Brown discharge in the third week of pregnancy may also be due to maternal disease, the embryo’s own factors, external factors, such as the phenomenon of pre-eclampsia, there will be brown discharge, abdominal pain, lumbar pain and other discomforts. 3. Ectopic pregnancy. 3 weeks pregnant with brown discharge should also be alert to whether the fertilized egg in the uterus after the embryo can not be normal development, as well as low levels of hormones can not maintain the growth of the endometrium, resulting in part of the endometrium shedding caused by bleeding. 4. Gynecological diseases. Be alert to whether cervicitis or cervical polyps and other diseases caused by irregular bleeding, to determine the cause of the brown discharge and the location of the symptomatic treatment. If you feel unwell during pregnancy, it is recommended that you seek medical attention as soon as possible.