Template:Short description Template:Infobox artery The umbilical artery is a paired artery (with one for each half of the body) that is found in the abdominal and pelvic regions. In the fetus, it extends into the umbilical cord.
StructureEdit
DevelopmentEdit
The umbilical arteries supply systemic arterial blood from the fetus to the placenta. Although this blood is sometimes referred to as deoxygenated blood it is not, and has the same oxygen saturation and nutrients as blood distributed to the other fetal tissues. There are usually two umbilical arteries present together with one umbilical vein in the umbilical cord. The umbilical arteries surround the urinary bladder and then carry all the deoxygenated blood out of the fetus through the umbilical cord. Inside the placenta, the umbilical arteries connect with each other at a distance of approximately 5 mm from the cord insertion in what is called the Hyrtl anastomosis.<ref>Template:Cite journal</ref> Subsequently, they branch into chorionic arteries or intraplacental fetal arteries.<ref>Template:Cite journal</ref>
The umbilical arteries are actually the anterior division of the internal iliac arteries, and retain part of this function after birth.<ref>Template:Citation</ref>
The umbilical arteries are one of two arteries in the human body that carry deoxygenated blood, the other being the pulmonary arteries.
The pressure inside the umbilical artery is approximately 50 mmHg.<ref>Fetal and maternal blood circulation systems From Online course in embryology for medicine students. Universities of Fribourg, Lausanne and Bern (Switzerland). Retrieved on 6 April 2009</ref> Resistance to blood flow decreases during development as the artery grows wider.<ref>Template:Citation</ref>
After developmentEdit
The umbilical artery regresses after birth. A portion obliterates to become the medial umbilical ligament (not to be confused with the median umbilical ligament, a different structure that represents the remnant of the embryonic urachus). A portion remains open as a branch of the anterior division of the internal iliac artery. The umbilical artery is found in the pelvis, and gives rise to the superior vesical arteries, which in males usually supplies the artery to the ductus deferens. Alternately, the latter artery can be supplied by the inferior vesical artery in some individuals.
Clinical significanceEdit
A catheter may be inserted into one of the umbilical arteries of critically ill babies for drawing blood for testing.<ref name=":0">Template:Citation</ref> This is a common procedure in neonatal intensive care, and can often be performed until 2 weeks after birth (when the arteries start to decay too much).<ref>Template:Citation</ref> The umbilical arteries are typically not suitable for infusions.<ref name=":0" /><ref>Template:Citation</ref>
Additional imagesEdit
- Gray31.png
Model of human embryo, 1.3 mm. long.
- Gray1111.png
Transverse section of human embryo, eight and a half to nine weeks old.
- Gray1115.png
Tail end of human embryo, twenty-five to twenty-nine days old.
- Inguinal fossae.PNG
Inguinal fossae
- Slide4khi.JPG
Umbilical artery. Deep dissection. Anterior view.
- Slide4BLA.JPG
Umbilical artery. Deep dissection. Serial cross-section.
See alsoEdit
ReferencesEdit
External linksEdit
- Template:SUNYAnatomyLabs - "The Female Pelvis: Branches of Internal Iliac Artery"
Template:Arteries of thorax and abdomen Template:Extraembryonic and fetal membranes Template:Development of circulatory system Template:Authority control