Anterior vascularization is also known as anterior vascularization, and anterior vascularization can usually be detected by 4D ultrasound. There is no direct connection between the placenta and the umbilical cord after pregnancy, the membranous placenta is connected through the membranes, if the blood vessels on the membranes are located in front of the fetal prenatal exposure across the cervical opening, it is called anterior vascularization. Generally, 4D ultrasound can find the presence or absence of anterior vascularization. 4D ultrasound will first determine the shape of the placenta, and then further observe the relationship between the umbilical vessels and the endocervical os, so as to determine the anterior vascularization. Pregnant women with anterior vascularization, when the umbilical blood vessels are easily squeezed by the fetal head during contractions or when rupture of membranes occurs, it may cause rupture of the blood vessels, obstruction of the circulation of the umbilical cord blood flow, loss of blood to the fetus causing fetal distress, and in severe cases, fetal death in the uterus. After pregnancy, you need to do a good job of regular pregnancy checkups, abnormalities can be detected in a timely manner.