Estriol can be measured in maternal blood or urine and can be used as a marker of fetal health and well - being. If levels of unconjugated estriol (uE3 or free estriol) are abnormally low in a pregnant woman, this may indicate chromosomal or congenital anomalies like Down syndrome or Edward 's syndrome. It is included as part of the triple test and quadruple test for antenatal screening for fetal anomalies.
decreased estriol levels in pregnancy are associated with
chromosomal or congenital anomalies like Down syndrome or Edward 's syndrome