Vaginal bleeding can be brown if the bleeding is small, if the blood stays in the vagina for a long time or if there is bleeding from the uterine cavity. In order to identify the cause of brown blood, it is necessary to confirm the site of bleeding (e.g., in the cervix or uterine cavity) and to further determine the cause of bleeding. 1. For patients who have a history of cervical lesions and are pregnant for more than one month (excluding bleeding from the fertilized egg), if there is a small amount of vaginal bleeding without abdominal pain and the ultrasound examination indicates no abnormalities in the intrauterine sac, we should examine the cervix with a vaginal speculum and if we see bleeding from cervical lesions, we should mainly consider that the vaginal bleeding is due to cervical lesions. If there is little bleeding, it should be left untreated and if necessary, treatment should be given to stop bleeding and prevent infection. 2.For pregnant women with a small gestational period (less than one month of pregnancy), if there is a small amount of vaginal bleeding without abdominal pain, the ultrasound examination indicates that there is no abnormality in the intrauterine fetal sac and the cervical examination is normal, the main consideration is that the fertilized egg is in the womb after pregnancy, which is a manifestation of abnormal fertilization of the fertilized egg due to physiological problems in a small number of people; this kind of bleeding does not require treatment and can be kept clean and has no obvious effect on the development of the pregnant embryo. 3. If the above two conditions of vaginal bleeding have been excluded, when the patient has no abnormal early pregnancy ultrasound, but irregular small amount of brown blood in the vagina, no abdominal pain or vague abdominal pain, consider pre-eclampsia abortion, if there are no obvious external factors (external impact on the abdomen, coitus, etc.), mainly due to insufficient hormone level (mainly refers to HCG or progesterone), light bed rest, if there is no relief, can be given fetal preservation treatment.