Low levels of estriol are associated with which trisomy?

Low levels of estriol are particularly associated with Trisomy 18, also known as Edwards syndrome. Estriol is a type of estrogen that is produced in significant amounts during pregnancy. In the context of prenatal screening, decreased levels of maternal serum estriol are part of the biochemical markers used to assess the risk of certain fetal aneuploidies.

Specifically, for mothers carrying a fetus with Trisomy 18, the production of estriol is typically reduced due to the abnormal fetal development associated with the condition. Screening markers, including estriol, are commonly utilized in first and second-trimester maternal serum screenings to evaluate the risk for chromosomal abnormalities.

In contrast, other trisomies such as Trisomy 21 (Down syndrome) have a different pattern of biochemical markers, where estriol levels may not be as significantly lowered. Thus, the connection between low estriol levels and Trisomy 18 allows healthcare providers to make informed decisions for further testing and management of the pregnancy.