First Trimester Screen hCG


Test Code

Quest Code

CPT Codes
81508<br /> This test is for non-New York clients. For New York patient testing, use test code 16968

PAPP-A (Pregnancy-associated Plasma Protein-A), hCG, Maternal Risk calculation which includes NT (Nuchal Translucency)

Preferred Specimen
1.5 mL serum

Minimum Volume
0.8 mL

Collect between 10.0 weeks to 13.9 (13 6/7) weeks. Perform between 10.0 to 13.9 (13 6/7) weeks gestational age. A special Maternal Serum Screen requisition designed to obtain patient data and the patient's informed consent must be used when ordering this test, because these results are influenced by certain patient characteristics. All data requested on the requisition form must be complete to permit accurate interpretation of results.

Transport Container
Plastic screw-cap vial

Transport Temperature

Room temperature

Specimen Stability
Room temperature: 14 days
Refrigerated: 14 days
Frozen: 28 days

Reject Criteria (Eg, hemolysis? Lipemia? Thaw/Other?)
Gross hemolysis

Calculation (CALC) • Chemiluminescence (CL) • Immunoassay (IA)

FDA Status
*PAPP-A Component only: This test was performed using a kit that has not been cleared or approved by the FDA. The analytical performance characteristics of this test have been determined by Quest Diagnostics. This test should not be used for diagnosis without confirmation by other medically established means.

Setup Schedule
Set up: Mon-Sat; Report available: 4-6 days

First Trimester Screen results consistent with increased risk of trisomy should be confirmed with CVS or amniotic fluid specimen. Maternal serum screening yields a low percentage of false negatives. A wide range of other chromosomal abnormalities are not identified by maternal serum screening.

Reference Range
MSS Down Syndrome Risk: <1:270
MSS Trisomy 18 Risk: <1:100

Clinical Significance
To screen for Down Syndrome and Trisomy 18 at 10.0-13.9 weeks gestation.

Performing Laboratory
Quest Diagnostics Nichols Institute-San Juan Capistrano, CA
33608 Ortega Highway
San Juan Capistrano, CA 92675-2042

The CPT Codes provided in this document are based on AMA guidelines and are for informational purposes only. CPT coding is the sole responsibility of the billing party. Please direct any questions regarding coding to the payor being billed. Any Profile/panel component may be ordered separately. Reflex tests are performed at an additional charge.