A small amount of fresh blood at 5 weeks of pregnancy is usually abnormal and may be due to ectopic pregnancy, preeclampsia and other reasons. 1. Ectopic pregnancy: The fertilized egg is deposited outside the uterine cavity due to pelvic inflammation, history of tubal surgery, assisted reproduction techniques, etc. Most ectopic pregnancies are tubal pregnancies. Most ectopic pregnancies are tubal pregnancies. In tubal pregnancies, the meconium inside the uterus will be shed, which may cause a small amount of bleeding, bright red in color, which is a pathological condition and not a normal condition. 2. Pre-eclampsia: pregnant women with anemia, viral infections, high fever, exposure to large amounts of radioactive substances, embryonic genetic abnormalities and other reasons lead to women 5 weeks pregnant with pre-eclampsia, there will be a small amount of bleeding, bright red, bleeding accompanied by abdominal pain, and may develop into a difficult to avoid abortion. A small amount of fresh blood in the 5th week of pregnancy should be consulted promptly, and the cause should be identified and appropriate treatment given under the guidance of the doctor.