Test Code LAB144 Human Chorionic Gonadotropin (hCG), Qualitative, Blood
Performing Laboratory
St. Louis Children's Hospital Laboratory - Chemistry
Specimen Requirements
Patient Preparation: None
NOTE: this test is for specimen samples on females only. Specimens for males will not be analyzed by this method. See "Human Chorionic Gonadotropin (hCG), Quantitative Serum" if hCG level required for male patient.
Collection Container/Tube:
Preferred: Gold SST gel tube
Acceptable: Plain red-top tube
Submission Container/Tube: If specimen is coming from outside facility and collected in a plain red-top tube or EDTA tube aliquot processed sample into a plastic vial for transport (labeling with specimen type).
Specimen Collection Volume: 2.0 mL (minimum 0.5 mL)
Special Instructions: Send to lab promptly.
Sample Rejection
Mislabled or unlabeled specimens
Specimens that are grossly hemolyzed
Specimens submitted on male patients
Logistics
Test Availability: Monday-Sunday
Cut-off time: None; performed as received
Turnaround Time: Same Day; 30 minutes from receipt in lab
Reference Values
Reference Interval: Reported as Positive or Negative
Critical Value: None established
Methodology
Rapid solid-phase, Chromatographic immunoassay
Limitations
-
False negative results may occur when the levels of hCG are below the sensitivity level of the test. When pregnancy is still suspected, a first morning specimen should be collected 48 hours later and retested.
-
As with any assay employing mouse antibodies, the possibility exists for interference by human anti-mouse antibodies (HAMA) in the specimen. Specimens from patients who have received preparations of monoclonal antibodies for diagnosis or therapy may contain HAMA. Such specimens may cause false positive or false negative results.
Additional Information
FOR SLCH CORE LABORATORY USE ONLY
Lab Processing Instructions: Centrifuge to separate. If specimen is collected in a plain red-top tube aliquot sample into screw-cap, plastic vial for testing (labeling aliquot with specimen type).
Processed Volume: minimum 0.2 mL serum
Analyte Stability:
Specimen Type | Temperature | Time |
---|---|---|
Whole Blood (unprocessed) | Ambient | 1 hours |
Plasma/Serum (processed) | Refrigerated (preferred) | 2 days |
Ambient | 1 hours | |
Frozen | 1 year |
Test Classification and CPT Code
84703
LOINC
2118-8
Last Reviewed
08/2025