A low placenta in pregnancy may cause vaginal bleeding, fetal hypoxia, and premature birth. The effects caused by a low placenta depend on the different trimesters in which the low placenta position occurs. If the placenta is found to be low on ultrasound before the 28th week of pregnancy, in most cases there is no need to worry too much. As the lower part of the uterus continues to elongate in the middle and late stages of pregnancy, in most cases the placenta will be located further and further from the inner cervical opening. By about 28 weeks of pregnancy, most of the cases of low placenta position can be improved significantly. If the placenta is still low or placenta praevia at 28 weeks, because the lower part of the uterus gradually stretches in late pregnancy, the cervical canal disappears and the opening of the uterus dilates after delivery, but the placenta attached to the lower part of the uterus or the inner cervical opening does not stretch accordingly and bleeding from abruption occurs. Repeated bleeding for a long time may lead to anemia or secondary infection, and a large amount of bleeding may lead to hemorrhagic shock, which may endanger the life of mother and child. In addition, a low placenta has an impact on the postpartum period, because the placenta is attached to the surgical incision, making it difficult to operate and bleeding, and the uterus is poorly contracted, making it difficult to control bleeding, with a high chance of hemorrhage and making the mother prone to puerperal infection and even death. If the placenta is found to be low during pregnancy, it is important to take proper rest, avoid strenuous activities, prohibit sexual intercourse, have regular maternity checkups and be hospitalized if there is recurrent vaginal bleeding.