Brown discharge in the first month of pregnancy may be normal, or it may be caused by pre-eclampsia, ectopic pregnancy or biochemical pregnancy. 1. Normal: Pregnant women one month pregnant in the process of fertilized egg implantation, may lead to endometrial blood vessel rupture, causing a small amount of vaginal bleeding. 2. Pre-eclampsia: If a pregnant woman is affected by various external adverse factors in the early stage of pregnancy, it may lead to unstable embryo implantation and symptoms of pre-eclampsia, such as vaginal bleeding, abdominal pain and so on. 3. Ectopic pregnancy: if the embryo is deposited in the fallopian tube and other non-uterine cavity in the normal position, it is easy to cause local tissue rupture and bleeding and related symptoms. 4. Biochemical pregnancy: If the fertilized egg is not deposited in the uterine lining and is directly expelled from the body, this situation will also lead to vaginal bleeding and related symptoms. If a pregnant woman experiences abdominal pain or vaginal bleeding in early pregnancy, she must go to the hospital as soon as possible to find out the cause.