Low placenta in pregnancy may trigger vaginal bleeding, lack of oxygen to the fetus, and premature labor. The effects of 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, the placenta will in most cases be farther and farther away from the cervical opening. In most cases, the placenta will be farther away from the cervical os. By about 28 weeks of pregnancy, the majority of cases of low lying placenta will have 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 after labor, the mouth of the uterus expands, and the placenta attached to the lower part of the uterus or the cervical os is not able to stretch accordingly, and then peeling off the bleeding occurs. Repeated bleeding over a long period of time may lead to anemia or secondary infection, and a large amount of bleeding may lead to hemorrhagic shock, endangering the lives of both mother and child. In addition, a low placenta also has an impact on the delivery and postpartum period, because the placenta is attached to the surgical incision leading to difficulties in surgery, bleeding, and poor uterine contraction, bleeding is difficult to control, the chances of hemorrhage are high, and the mother is susceptible to puerperal infections and even death. If the placenta is found to be in a low position during pregnancy, it is necessary to take proper rest, avoid strenuous activities, prohibit sexual intercourse, undergo regular checkups, and be hospitalized if there is recurrent vaginal bleeding.