Umbilical cord Umbilical cord In placental mammals, the umbilical cord (also called the navel string, birth cord or funiculus umbilicalis) is a conduit between the developing embryo or fetus and the placenta. During prenatal development, the umbilical cord is physiologically and genetically part of the fetus and (in humans) normally contains two arteries (the umbilical arteries) and one vein (the umbilical vein), buried within Wharton's jelly. The umbilical vein supplies the fetus with oxygenated, nutrient-rich blood from the placenta. Conversely, the fetal heart pumps low oxygen containing blood, nutrient-depleted blood through the umbilical arteries back to the placenta. The umbilical cord develops
Percutaneous umbilical cord blood sampling preexisting defects and abnormalities. While ultrasounds and color flow mapping can be used to avoid the umbilical artery and sample from the umbilical vein, the dilation makes the single umbilical artery easier to puncture. Blood flow in the umbilical artery is seen to be twice the normal amount from about 20 weeks on so the effects of a punctured umbilical artery during PUBS are more severe. Percutaneous umbilical cord blood sampling "For other uses see PUBS ( page)" Percutaneous umbilical cord blood sampling (PUBS), also called cordocentesis, fetal blood sampling, or umbilical vein sampling is a diagnostic genetic test that