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Single umbilical artery

Martin L Gimovsky, MD
Eva Tejero Rosa, MS, CGC
Waldo Sepulveda, MD
Section Editors
Deborah Levine, MD
Louise Wilkins-Haug, MD, PhD
Deputy Editor
Vanessa A Barss, MD, FACOG


The umbilical cord typically contains two arteries and one vein. Single umbilical artery (SUA) refers to a variation of umbilical cord anatomy in which there is only one umbilical artery. It may be an isolated finding, or associated with aneuploidy or other congenital anomalies.


Three mechanisms have been proposed to explain the development of SUA [1]:

Secondary atresia or atrophy of a previously normal umbilical artery

Primary agenesis of one of the umbilical arteries

Persistence of the original single allantoic artery of the body stalk

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Literature review current through: Nov 2017. | This topic last updated: Dec 01, 2016.
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