In the fourth week of pregnancy, the lower edge of the placenta is adjacent to the endocervical os and there is a lot of bleeding which requires hospitalization as soon as possible, and needs to be treated with fertility preservation or termination of pregnancy. The placenta plays an important role in the development and growth of the fetus, and when the lower edge of the placenta is adjacent to the endocervical os and there is a lot of bleeding, it belongs to the marginal placenta praevia. At this time, if the fetus survives in the uterus, the general condition is good, and the vaginal bleeding is less than the amount of previous menstrual periods, you can follow the doctor’s instructions to give birth control treatment, such as magnesium sulfate to inhibit contractions; when accompanied by anemia, you can be given ferrous succinate tablets and other treatments. Fertility preservation process must be carried out under the close supervision of doctors and nurses, if there is persistent bleeding or bleeding greater than the amount of menstruation, pregnant women appear hemorrhagic shock, in order to save the life of the pregnant woman, you can follow the doctor’s advice to terminate the pregnancy at the right time. If a woman experiences lower abdominal pain or vaginal bleeding after pregnancy, she should go to the hospital in time and follow the doctor’s instructions for active treatment after being examined by a professional doctor.