Umbilical Cord Blood.

In placental mammals, the umbilical cord is a tube that connects a developing embryo or fetus to the placenta. It normally contains three vessels, two arteries and one vein, buried within Wharton's jelly, for the exchange of nutrient- and oxygen-rich blood between the embryo and placenta. The presence of only two vessels in the cord is sometimes related to abnormalities in the fetus, but may occur without accompanying abnormalities.

The umbilical cord develops from, and contains, remnants of the yolk sac and allantois. In humans, the umbilical cord in a full term neonate is usually about 50 cm long and about 2 cm in diameter.

A newborn with cord stump still visible after 7 days.

In the third stage of labour, after the child is born, the uterus spontaneously expels the neonate's placenta along with the cord from the mother's body, 10-45 minutes after the birth. However, the umbilical cord is generally clamped during or within minutes of birth and severed shortly after, a practice of "active management of labor" which has become increasingly controversial due to the lower transfer of placental blood to the neonate and associated stressors. The health benefits of non-clamping of the cord and delayed umbilical severance as well as nonseverance are receiving attention in medical journals.^{[citation needed]}

After the cord is clamped and cut (Western obstetrical protocol) the newborn wears a plastic clip on the navel area, where the remaining umbilical stub remains for up to 2-3 weeks until it falls off. In nonseverance scenarios, also called Lotus Birth, the umbilical cord is wrapped up to within an inch of the newborn's belly, and dries and naturally separates.

Makeup and composition

The umbilical cord is made of Wharton's jelly, not ordinary skin and connective tissue. There are no nerves, so cutting it is not painful. There is ordinarily no significant loss of either infant or maternal blood while cutting the cord. In many Western cultures the umbilical cord is traditionally cut by the father of the baby. The cord contains two arteries which carry deoxygenated blood (from the fetus back to the mother) and one vein that carries oxygenated blood (from the mother to the fetus). Today there are umbilical cord clamps which combine the cord clamps with the knife. These clamps are safer and faster, allowing one to first insert the cord clamp and then cut the umbilical cord.

Resource:http://en.wikipedia.org/wiki/Umbilical_cord