If the lower edge of the placenta reaches the endocervix in late pregnancy and causes bleeding, it is considered to be placenta praevia. If it is only borderline, it can be observed first; if it is partial or central type, cesarean section is needed to terminate the pregnancy. 1. Marginal placenta previa: If painless vaginal bleeding occurs in late pregnancy, regular checkups in obstetrics clinic are needed. In most cases, it is marginal placenta previa, i.e., the edge of the placenta reaches to cover the cervical endocervix. The amount of bleeding is small, and during the observation period, one should avoid exertion and strenuous exercise to prevent the peeling surface of the placenta from the uterine wall from increasing. 2. Central, partial placenta previa: the lower edge of the placenta covers more of the endocervical os, and an increase in the number of gestational weeks may lead to obvious detachment of the placenta from the uterine wall, which in turn leads to heavy vaginal bleeding and needs to be taken seriously. Early termination of pregnancy is usually required at around 37 weeks. If heavy bleeding occurs during this period, rapid cesarean section is required to terminate the pregnancy. Therefore, it is recommended to pay attention to women who have bleeding from the lower edge of the placenta up to the endocervical os during the labor and delivery examination, arrange the labor and delivery examination time reasonably under the guidance of the doctor, and pay close attention to the situation of vaginal bleeding. If the placenta is borderline placenta praevia, normal delivery can still be chosen; if the placenta is central or partial placenta praevia, it is recommended to terminate the pregnancy by cesarean section under the guidance of the doctor to avoid the occurrence of adverse prognosis.