Estriol, LC/MS/MS, Serum
Estriol may sometimes be ordered serially to help monitor a high risk pregnancy. When it is used this way, each sample should be drawn at the same time each day. An unconjugated estriol test, one that measures estriol that is not bound to a protein, is one of the components of the triple or quad screen. Decreased levels have been associated with various genetic disorders including Down syndrome, neural tube defects, and adrenal abnormalities. It is ordered during pregnancy, along with maternal alpha-fetoprotein (AFP maternal), human chorionic gonadotropin (hCG), and inhibin-A tests, to assess the risk of carrying a fetus with certain abnormalities.