What is the umbilical cord?

“The umbilical cord is very important because it is the baby’s lifeline. It brings everything that the baby needs to grow and be healthy from the mother. Then the baby sends back the used carbon dioxide, his waste products, to mom and to that umbilical cord, and her body disposes of them.

It has a very interesting shape and composition because it’s made out of this Wharton’s jelly, which is full of mesenchymal STEM cells. The Wharton’s jelly helps to protect the blood vessels in the umbilical cord from getting shut off or the flow interrupted because it makes the cord very full and round. So the baby can’t squeeze it. It is very unlikely that the fetus will push up against it and the uterus, so it protects it. The Wharton’s jelly protects it from being shut off.”

Clamping the Cord

And as a baby comes down the birth canal, the cord continues this function of exchanging the nutrients and this function continues for a while after the baby’s born. So the baby continues to get oxygen for at least a couple of minutes after he’s born through the cord. If we leave the cord attached to the placenta and the baby until the placenta is ready to deliver, then the baby gets all of his blood from the placenta that he needs.

Maternal Health Effects

The umbilical cord is really the baby’s lifeline. And it is very interesting because you see in women who eat very well and take care of themselves and are healthy, that the umbilical cord is usually nice and full at birth. And then sometimes when there’s been problems or issues, the cord is very thin and not as protective of the infants. Anyway, it plays an extremely important role; it is the fetus’s lifeline during the pregnancy.”

Additional Resources


ASK: What is delayed cord clamping?

ASK: Should I collect my baby’s stem cells instead of delaying the clamping of the umbilical cord?


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Since joining the faculty at the University of Rhode Island in 1998, Dr. Mercer has continued her commitments to teach midwifery and other students, provide midwifery care through the URI Center for Midwifery at Memorial Hospital of Rhode Island in Pawtucket, and carry out her research examining... Read More