Genetics Northern California

Glossary

TermDescription
Ultrasound

The use of sound waves to visualize soft tissue organs and fetuses (also known as sonogram).

Uncongugated estriol

Unconjugated estriol (uE3) is a hormone produced by the placenta and the developing baby. Levels rise throughout normal pregnancy. Maternal blood levels of uE3 may be lower in a pregnancy if the baby is affected with Down syndrome or trisomy 18 or SLOS.

Urea Cycle DisordersUrea Cycle Disorders (UCDs) occur when there is a defect in one of the enzymes needed to remove nitrogen from the blood. This process is called the "urea cycle" and if it is not working properly, ammonia levels in the blood rise causing damage to nearly every organ in the body. This can lead to developmental delays, irreversible brain damage and/or death. There are several types of UCDs and they vary in severity.