Bleeding in early pregnancy can be caused by bleeding from fertilized egg implantation, pre-eclampsia, ectopic pregnancy, gravida, pregnancy combined with vaginal and cervical lesions and external stimulation. 1.Bed-breeding bleeding of fertilized egg: After the fertilized egg is formed in the fallopian tube, it needs to move to the uterus and then choose a suitable location in the uterine cavity for further development, which is called bed-breeding. During the process of fertilization, the endometrium of the uterus will be destroyed and some pregnant women may experience a small amount of vaginal bleeding or brown discharge, which is a normal phenomenon. 2. Pre-eclampsia: If the patient has been diagnosed with intrauterine pregnancy in the past and has irregular vaginal bleeding in the early stage of pregnancy, without abdominal pain or abdominal pain, without obvious external factors (external impact on the abdomen, intercourse, etc.), except for vaginal and cervical lesions, consider pre-eclampsia, such bleeding is often related to insufficient hormone levels (HCG or progesterone), and progesterone treatment should be given. 3.If the pregnant woman has not clearly intrauterine early pregnancy in the past: only positive urine test paper at home, bleeding in early pregnancy does not exclude the possibility of ectopic pregnancy, which can be accompanied by abdominal pain, abdominal mass, or even syncope and shock, and need to go to the hospital for a clear diagnosis and appropriate treatment. 4.Gravida: If a pregnant woman has abnormal enlargement and softening of the uterus in addition to vaginal bleeding, early and severe pregnancy vomiting, or even combined with hypertension and edema, she should be alert to bleeding caused by gravida. In summary, regardless of the cause of bleeding during pregnancy, it is necessary to seek medical attention in a timely manner, especially for pregnant women with undetermined intrauterine pregnancy, who need to be alert to bleeding caused by ectopic pregnancy and need to seek medical attention as soon as possible for a clear diagnosis.