The essential link between mother and baby explained
The 50-centimetre (20-inch)-long umbilical cord runs from the centre of the mother’s placenta to an opening in the baby’s stomach. It consists of an umbilical vein and two arteries, which spiral around it.
The vein supplies the baby with nutrients and oxygenated blood from the mother’s placenta, while the two arteries return carbon dioxide and other waste products and deoxygenated blood back to the placenta. They are coated with protective Wharton’s jelly, and sheathed with a smooth transparent membrane called amnion.
The maternal blood supply divides inside the baby to distribute blood to the liver and heart. This oxygenated blood circulates rapidly to renew the baby’s oxygen levels, and this role is taken over by the lungs after birth.
Umbilical cord facts
Placenta – The placenta stores and provides oxygen, nutrients and hormones to the baby, as well as processing the returned waste products.
Chorionic plate – The umbilical blood vessels spread over the chorionic plate and descend like tree roots, deep into the placenta.
Wharton’s jelly – The bloodvessels are covered in this sticky substance and protected by the amnion membrane.
Blood vessels – The one oxygenated vein supplies blood from the placenta, and the two arteries return deoxygenated blood and waste to it.