The placenta is an organ that plays a critical role in the development of the fetus. The placenta begins to form at the moment when the fetal egg is attached to the wall of the uterus, and by the twelve weeks of pregnancy, it takes on nutritional, respiratory, excretory, protective and hormonal functions.
Usually, the placenta is located in the fundus of the uterus or along its back with a transition to the side walls, less often - along the front wall. But there is such a pathology as placenta previa. The placenta, located in the lower part of the uterus, covers its internal pharynx partially or completely. Depending on this, there are complete (central), partial and low placenta previa.
Complete placenta previa, when the cervix is completely blocked, is quite rare. Partial placenta previa can be marginal and lateral. Marginal placenta previa is the location of the placenta, in which the internal os is closed by one third; lateral presentation - when two thirds are closed. With low placenta previa, this important organ is located at a distance of no more than fivecentimeters from the internal os. But low placentation is considered a pathology only in the third trimester of pregnancy, before that time the placenta may well rise.
The main reason placenta previa occurs is that the lining of the uterus has undergone changes that prevent the fertilized egg from attaching properly. These changes may occur as a result of an inflammatory process, the use of intrauterine devices, endometrial disorders due to abortion or intrauterine curettage, uterine fibroids. Of all the cases when doctors diagnose marginal placenta previa, 75% occur in women who are pregnant again. Also, diseases of the internal organs of a pregnant woman can affect the incorrect fixation of the embryo.
A clinical symptom, which determines both marginal placenta previa and other types of its incorrect location, is bleeding from the genital tract, accompanied by pain. It can occur at different stages of pregnancy - both in the first trimester and just before childbirth. The cause of bleeding is a partial detachment of the placenta. The walls of the uterus during pregnancy are stretched, and the placenta is not capable of such stretching, as a result, its detachment occurs.
If medical measures are not taken in time, the fetus will begin to experience hypoxia, and the pregnant woman may develop significant anemia. Sometimes bleeding can even becomecause of death. Therefore, if a gynecologist detects lateral, complete or marginal placenta previa, it is necessary to strictly follow his instructions. Focusing on the complaints of a pregnant woman and the results of an ultrasound scan, he will prescribe bed rest, drugs for uterine contraction, in case of frequent repeated bleeding, hospitalization and treatment in a hospital. Delivery will most likely be by caesarean section, only the marginal location of the placenta leaves room for natural delivery.
