SINGLE ARTERY UMBILICAL CORD

About 30 years ago, a baby boy was born at home in a town about 90 minutes drive away from where I lived in Vancouver, BC. All was normal with the birth (first baby for the family). The baby was about 8 pounds and he seemed healthy.

I was taught to inspect every placenta carefully at some point in the hours after birth. One part of the placenta exam was to look at the cut end of the umbilical cord and make sure there were 3 little openings where the 2 arteries and one vein were. Remember, this was in the days pre-internet. Midwifery training was accessed by reading thick obstetric/midwifery text books in those days. This little boy’s umbilical cord had only 2 vessels. Oh no. Where was that third little opening for the second artery? I re-cut and peered at the end of the cord but, no, only two vessels. The only instructions in any of my textbooks about that possibility were to “call the pediatrician”. So, I did. At that time, we had a kind pediatrician who always took calls from home birth attendants. When I told him the situation, he said “Hmmmmm, I don’t know what that means. Could you go in to Children’s Hospital to the library and look it up?” I didn’t like to leave the family’s home without knowing for sure that the baby would be okay and I had that 90 mins between their home and the hospital library. I decided to call a friend who was a long time hospital nurse. She didn’t know either but thought it might have something to do with the heart. The baby wasn’t showing any signs of blueness around the mouth and was a keen breast feeder so, I didn’t see or hear any heart problem indicators. After a few hours, I headed back to town and went straight to the Hospital Library.

Vein larger than the 2 arteries

In those pre-computer days, the hospital Librarian was a God-send. She was very helpful and looked up a bunch of articles for me but they really didn’t tell me much more than “it could mean a kidney problem”. I was feeling frustrated but, then, got an idea. I could find the pathology department in the hospital and speak to a person who had seen babies with kidney problems and maybe get some useful help.

I was a bit nervous going to Pathology because I was afraid I’d see dead bodies but, no, the place was clean as could be. The Pathologist was glad to see me and have someone to talk to. (I think that’s a lonely job). I told him what was going on and the first question he asked was “How much did the baby weigh?” He then told me that babies with kidney problems tend to be very small so he doubted my finding that there were only two vessels in the umbilical cord of an 8 lb. baby. He suggested that I should bring the placenta in so he could take a look. I wasn’t relishing the 90 minute drive back and forth again but I was more than willing to be wrong about my count of the vessels if it meant I could relax about the baby.

One vein, two arteries

I returned to the family home, got the placenta from the fridge and drove it back to show the pathologist. He cut the end of the cord on his marble slab and peered at it and then said “Well, I see what you mean. There are just two but can you see that the vein, which is usually larger than the arteries, and the one other vessel are both about the same size? I think what happened here is that the two vessels grew together. If the baby is pee-ing normally and eating well, I don’t think you have anything to worry about.” He then proceeded to reach up on to his shelf and bring down a copy of a thick text book entitled “The Human Placenta”. He told me that it was a fascinating book by a pathologist who had been a veterinarian before he pursued pathology. When I expressed amazement that there was enough to say about the placenta that it could fill a whole book of its own, he said that a lot of the information was comparing the human placenta to that of zebras, gorillas, and other wild animals. Somehow, I’ve never been tempted to buy the book. . . I like to keep my placenta knowledge on a “need to know” basis.

That little boy did just fine and he’s a big man now. That’s the only 2 Vessel cord I’ve ever encountered in 1500 plus births, so it’s very rare (and, in this case, not even a real finding).
I hope this story is informative and reassuring to parents/practitioners about SUA (single umbilical artery) diagnoses in babies with normal growth.
Gloria Lemay, Vancouver BC Canada

From www.midwifethinking.com
A great blog