Test Directory

Estriol, Unconjugated, Serum

Print this page

Updated Test Information:

Test Description
Estriol, Unconjugated, Serum
Estriol, Unconjugated
Test ID
General Information
Useful for:
A part of the SEQF/ Sequential Maternal Screening, Part 2, Serum and QUAD / Quad Screen (Second Trimester)
Maternal, Serum in biochemical second trimester or cross-trimester screening for Down syndrome and trisomy 18 syndrome
A marker of fetal demise
An element in the prenatal diagnosis of disorders of fetal steroid metabolism, including Smith-Lemli-Opitz syndrome,
X-linked ichthyosis and contiguous gene syndrome (placental sulfatase deficiency disorders), aromatase deficiency, primary or secondary fetal adrenal insufficiency, and various forms of congenital adrenal hyperplasia
Assessment of preterm labor risk
Epidemiological studies of breast cancer risk in conjunction with measurement of estrone, estradiol, and various metabolites
Assessing estrogen metabolism, estrogen and estrogen-like medications, and other endogenous or exogenous factors impacting on estrogen metabolism in the context of other basic scientific and clinical studies
Specimen Type
Specimen Requirements
Refrigerated (preferred) 14 days
Frozen 90 days
Unacceptable Specimen Conditions
Gross hemolysis Reject
Gross lipemia OK
Immunoenzymatic Assay
Estimated TAT
1-3 days
Testing Schedule
CPT Code(s)
Minimum Sample Volume
0.5 mL
Reference Range
Males: <0.07 ng/mL
Females: <0.08 ng/mL
Performing Lab
LOINC Code(s)