Small amount of vaginal bleeding during early pregnancy is very common and is usually caused by the following possible diseases. Ectopic pregnancy: Ectopic pregnancy often leads to vaginal bleeding and abdominal pain on one side in early pregnancy, because ectopic pregnancy has the risk of rupture and bleeding, which can threaten the patient’s life in serious cases. 2. Indolent abortion: also known as embryonic arrest, is caused by adverse effects on the growth of the embryo during early pregnancy or by genetic defects of the embryo itself. After the embryo stops developing, some pregnant women have the feeling that the early pregnancy reaction disappears, and there may be no obvious symptoms. It may take 2-4 weeks before most patients start to experience symptoms of miscarriage, such as vaginal bleeding, and then go to the hospital. Ultrasound and tests such as HCG and progesterone are needed to determine embryonic arrest. Once the diagnosis of embryonic abortion is confirmed, the pregnancy should be terminated by cervical ablation. 3. Pre-eclampsia (the most common): It is a condition in which a little vaginal bleeding occurs before the 28th week of pregnancy, accompanied by slight lower abdominal pain or back pain, which may develop into miscarriage in some cases, but most of them can continue the pregnancy after proper treatment. If a little vaginal bleeding occurs during early pregnancy, the patient should not be too nervous. After expulsion of the above two conditions, bed rest and symptomatic treatment with progesterone will relieve most of the symptoms.