Umbilical cord

The umbilical cord (Latin funiculus umbilicalis ) connects in all mammals (except monotremes and marsupials ), including humans, the embryo or fetus in the womb through the placenta to the bloodstream of the mother or pregnant women. It thus represents the supply of nutrients and oxygen as well as the disposal of metabolic waste products such as carbon dioxide safely.

Design and function

Human umbilical cord is about 50-60 inches long with a full-term infants, 1.5-2 cm, usually spirally wound in diameter and surrounded by the amnion. They initially contains four blood vessels, of which the right umbilical vein between the 28th and 32nd day of embryonic development regresses. After the umbilical cord has usually three vessels, two umbilical arteries ( umbilical arteries ) that conduct kohlenstoffdioxidreiches and nutrient-poor blood from the child to the placenta, umbilical vein and a ( umbilical vein ), the blood passes from the placenta to the baby. Typical of the umbilical cord is the gelatinous connective tissue, which is responsible on one hand for the necessary flexibility while protecting against kinking when bending loads. It consists of fine collagens, few fibroblasts and large amounts of water-binding Hyaluronen ( Wharton 's jelly ).

If only one umbilical artery detected, one speaks of a singular umbilical artery. A cord having two vessels is considered a variant and relatively rarely occurs ( in human about one percent of the cases ); the risk of malformation either the chromosomes or to the organs is increased by 30-60%. Even short umbilical cords are associated with an increased risk of birth defects, such as if the movements of the fetuses were reduced due to disorders of the central nervous system or the muscular system. Long umbilical cords are associated with a risk of knots in the cord and Schnurprolaps.

Umbilical cord after birth

In humans, the umbilical cord is typically tied twice after birth and cut as soon as the blood has stopped in the umbilical cord to pulsate. This is usually five to ten minutes after the birth of the case. In almost all animals, the umbilical cord is bitten by the mother or she tears off by itself. The fall after the umbilical cord resulting residue ( after about three to ten days ) scar in the middle of the belly is the belly button. The umbilical cord is insensitive to pain, so the collection of cord blood for the infant is painless.

Stem cells can be extracted from the umbilical cord blood.

Complications

In pregnancy and during birth can lead to so-called umbilical cord complications, such as the Nabelschnurumschlingung, umbilical cord knots and umbilical cord prolapse, come. Also an omphalocele ( umbilical cord rupture, umbilical hernia ), a malformation of the child, is possible.

Others

In the technique specific supply hoses are also umbilical ( English for " umbilical cord " ) called cable. These are used for example in space during the refueling of rockets, or connect the space suit of a Astronautens with the life support systems during an outside board activity in space.