How is the Umbilical Cord Formed?

What is an Umbilical Cord?

The umbilical cord is the link connecting the fetus and placenta. The umbilical cord is also referred to as the lifeline of the two. By the fifth week of a woman's pregnancy, the umbilical cord is formed. The purpose of the umbilical cord is to shield the vessels that travel amid the fetus and placenta. If the fetal blood is compromised, the umbilical cord vessels can result in severe harmful effects on the well being of the fetus and newborn.

The Lifeline connecting the placenta and the fetus

The embryo is attached to the placenta through a linking stalk close to the end of the third week of fetal development. Near the 25th day, the yolk sac is formed and by the 28th day, the yolk sac is strained down to a vitelline vessel which is enclosed by an umbilical ring. Near the end of the fifth week the umbilical ring consists of a linking stalk that passes the allantois (excretory duct) which consists of two umbilical arteries and one vein.
The vitelline duct (yoke sac stalk) and a vessel that links to the intra- and extraembryonic coelomic cavities. Near the tenth week, the gastrointestinal tract develops and extends beyond all the way through the umbilical ring and forms a physiologically common herniation into the umbilical cord. Usually, the loops of bowel draw in near the end of the third month. There are times when term umbilical cords reveal the vitelline and allantoic ducts, as well as their connected vessels, particularly when the fetal end of the cord is inspected.

The umbilical cord usually contains two umbilical blood vessel arteries and one umbilical vein that are rooted within a free-moving, rich, proteoglycan matrix. This free-moving matrix is referred to as Wharton's jelly and provides protection to the very critical vascular sustenance that links and supports the fetus and the placenta, the umbilical cord. The Wharton's jelly has characteristics similar to a polyurethane pillow in that if you try to twist it, it is resistant to compression or any form of twisting.
One percent of umbilical cords may consist of just one artery as opposed to the usual two arteries and many of the newborn babies do not possess any noticeable health problems when born connected to an umbilical cord having only one artery.

umbilical cord knotting

The length of an umbilical cord is dependent upon fetus movements. The more the fetal moves, the longer the cord becomes and vice versa; the less the fetus moves, the shorter the umbilical will be. On a normal basis, the human umbilical cord extends to a length of about 60-70 cm at full term. A longer umbilical cord, however, is a great deal more vulnerable to knotting up and entangling around the fetus, particularly entangling the neck of the fetus. A longer cord can also end up outside of the uterus at some point during delivery of the baby which can result in the demise of the fetus. Therefore, it is very important to thoroughly examine and monitor the mother throughout the pregnancy. The length of the umbilical cord, whether short or long, does not affect fetal blood flow, however.