Unconjugated Oestriol Blood Test (uE3)

The Unconjugated Oestriol (uE3) Blood Test measures the level of unconjugated oestriol, a form of oestrogen produced primarily by the placenta during pregnancy. This test is typically used as part of second-trimester screening programmes, often alongside alpha-fetoprotein (AFP), human chorionic gonadotropin (hCG), and inhibin A, to assess the risk of fetal chromosomal abnormalities such as Down syndrome (trisomy 21) and Edwards syndrome (trisomy 18), as well as neural tube defects. It may also be used to monitor placental function in high-risk pregnancies.

Who is it for?
- Pregnant individuals in the second trimester (typically 15 to 22 weeks) who are undergoing routine prenatal screening.
- Those with a history of pregnancy complications or increased risk factors for fetal chromosomal abnormalities.
- Clinicians monitoring placental health in complicated pregnancies.

Biomarkers included
- Unconjugated oestriol (uE3)

Why it matters
Unconjugated oestriol is a key component of the triple and quadruple screening tests. Low levels can indicate an increased risk of fetal chromosomal abnormalities or placental insufficiency, while high levels may be associated with multiple pregnancies or other conditions. Early detection through screening allows for further diagnostic testing and informed decision-making, helping to ensure the best possible outcomes for both mother and baby.