What does four-dimensional examination placenta mean?

A low placental position is a B-ultrasound diagnosis. If the placenta covers the internal opening of the cervix, it is called complete placenta previa. If the placenta does not cover the internal opening of the cervix, but the position is low, and the placental margin is within 2.5 cm of the internal opening of the cervix, it is called marginal placenta previa or placenta low. Both conditions are collectively called placenta previa. Placenta previa is diagnosed before 28 weeks of pregnancy as placenta previa, because there are many such patients with the progress of pregnancy, the fundus gradually rises, the placenta will be pulled up into the normal position of the placenta. If you show obvious uterine contractions accompanied by abdominal pain during pregnancy, you must see a doctor in time. If you show vaginal bleeding, you should see a doctor in time. According to the amount of bleeding, the danger to pregnant women and the danger to children, judge the next step of treatment.