Single umbilical artery

insideAbout 1 percent of singleton and about 5 percent of multiple pregnancies (twins, triplets or more) have an umbilical cord that contains only two blood vessels, instead of the normal three. The cause of this abnormality, called single umbilical artery, is unknown.

The umbilical cord is the life-line that attaches the mother and developing baby. Connecting through the placenta, a normal umbilical cord is made up of three blood vessels. One large vein carries oxygen and nutrient-rich blood to the baby and the two smaller arteries carry blood and waste products back to the placenta. The umbilical cord normally grows to about two feet in length, allowing the baby enough cord to safely move around without causing damage to the cord or the placenta.

In a single umbilical artery, one artery is missing. Studies suggest that babies with single umbilical artery have an increased risk for birth defects, including heart, central nervous system and urinary-tract defects and chromosomal abnormalities. A woman whose baby is diagnosed with single umbilical artery during a routine ultrasound may be offered certain prenatal tests to diagnose or rule out birth defects. These tests may include a detailed ultrasoundamniocentesis (to check for chromosomal abnormalities) and in some cases, echocardiography (a special type of ultrasound to evaluate the fetal heart). The provider also may recommend that the baby have an ultrasound after birth.

The diagnosis of a single umbilical artery does not necessarily mean that the baby will have a birth defect. It does mean, however, that some tests are warranted and that closer attention needs to be paid for the remainder of the pregnancy.

COMMENTS (9)

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    I just found out a month ago I had the one atery.. im scared can someone tell me about it please??

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    I was told I have SUA this past Thursday (Feb. 7th). I’m beyond scared for what the future holds. So far no signs of abnormbilities. Just have to have ultrasounds often to check on babys growth, and heart. Next ultrasound for me is March 7th.

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    It’s so hard to be patient in a situation like this. The most important thing is to keep all your prenatal care appointments and follow your health care provider’s advice. Make sure you write down all of your questions and take them with you to your appointments. This way you will know as much as you can about how everything is going. Hang in there!

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    Just wanted to comment that this abnormality is the most common umbilical cord abnormality and most babies will still be perfectly normal. With my first child they didn’t discover this issue until after he was born (which was a bonus since I didn’t have to worry about it through the pregnancy!) and he scored all 10’s on his apgars, and is now 4 years old with no health issues. Just wanted to encourage you that most likely everything is fine! I hope all tests come back with flying colors and you can enjoy the rest of your pregnancy!

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    Clarissa July 9, 2013

    I was diagnosed with a single umbilical artery 20 weeks. I was concerned, did my research and tried to stay positive throughout the rest of the pregnancy as there were no other abnormalities seen in the ultrasound. My baby was born March 28, 2013 and he’s perfectly healthy and amazing. He is now three months old and has hit all of his developmental milestones early or on time. Try not to worry and stay positive moms!

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    Found out my baby had sua at 24 wks everything checked fine the tech did an echo right away had a songram every month aft gave birth to a healthy 6lb.11oz. Girl 2 wks early shes 15 months now n perfectly normal!

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    I had a single umbilical artery also with my lil man i was so worried an stressed to.the max i couldnt sleep or anything my mind was just sat on something being wrong with my baby an all the coulds an ifs i also had slightly increased fluid about 33 weeks so i was really scared because that could mean somethings wrong also all my test come out normal they could not find any birth defects what so ever and my baby was born two weeks early april 16th 2013 6ponds 6oz so on the small side but he was healthy hes 7months now an has hit every milestone on time so just try to relax i know what you went through good luck

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    Melissa April 11, 2016

    I was diagnosed with the SUA, at times anxious about the outcomes, but even in Normal Pregnancies things can happen negatively. I try to be positive, go to growth scans every few weeks. Hang in there everyone.

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    Stephanie November 5, 2016

    I was also diagnosed with Sua and gestational diabetes while i was pregnant with my youngest daughter. She is now 2 years old and has some serious vision and speech delays is otherwise healthy though. Just wondering if any other parents who have babies with SUA have had similar issues.