脐带有两条动脉和一条静脉,从胎盘来的含营养物质丰富的血液通过脐静脉经胎儿体循环后,经降主动脉,脐动脉送至胎盘,与母血进行气体和物质的交换后,再由脐静脉送往胎儿体内。因为脐动脉是与胎儿的降主动脉相连的,所以脐动脉血流在临床上具有重要意义。某些病理情况下,脐动脉就可 Umbilical cord with two arteries and a vein from the placenta to the nutrient-rich blood through the umbilical vein through the fetal body circulation, the descending aorta, umbilical artery sent to the placenta, and maternal blood gas and substance exchange, and then From the umbilical vein to the fetus. Because the umbilical artery is connected with the descending aorta of the fetus, umbilical artery blood flow is clinically important. Under certain pathological conditions, umbilical arteries can be