Why do pregnant women have a single umbilical artery?

Women have a hard time after getting pregnant. They are very worried about some abnormal phenomena during pregnancy. Every pregnancy check-up is also very daunting. Some women's pregnancy process is not so smooth, such as the phenomenon of single umbilical artery. This phenomenon is rare, so why do pregnant women have single umbilical artery?

Why do pregnant women have a single umbilical artery?

1. Chromosomal abnormality. The cause of single umbilical artery is still unclear, but doctors believe that it may be related to fetal chromosomal abnormalities. Studies have shown that the detection rate of single umbilical artery chromosomal abnormalities is approximately 0.1%-0.2%. The detection rate of single umbilical artery in fetuses with chromosomal abnormalities is also quite high.

2. Umbilical artery hypoplasia during the embryonic period. During the embryonic period, the umbilical artery evolves from a pair of allantoic arteries that arise from the dorsal aorta. If one umbilical artery is poorly developed and atrophies, or if a single umbilical artery temporarily appears in the early stage (3.0-4.0mm embryonic pedicle) (i.e. the left and right umbilical arteries merge into one blood vessel) and this period persists, a single umbilical artery may result.

3. Blood clot. Thrombosis is also an important cause of single umbilical artery. Because the formation of blood clots may cause atrophy of one of the umbilical arteries, which will lead to the formation of a single umbilical artery over time.

What to do if a pregnant woman discovers a single umbilical artery

A single umbilical artery fetal abnormality cannot be prevented during a fetal malformation screening, but it does not necessarily mean that there is a problem with the fetus. Therefore, when a single umbilical artery is discovered, the expectant mother should go to the hospital for a fetal anomaly examination, including four-dimensional color ultrasound, fetal heart color ultrasound, and chromosome examination. If all tests are normal, then it is a normal pregnancy, just like a normal fetus.

However, there are exceptions to everything. If we find that there is a problem with the fetus during the examination, we recommend that female friends should make a judgment based on the actual situation and make a comprehensive choice. In addition, it should be determined whether serious deformities have occurred, in which case termination of pregnancy should be considered. In addition, since the baby has certain limitations during the examination process, we need to do a good job of observation afterwards, which is very important.