Home
HelpTest ID THCG Human Chorionic Gonadotropin (hCG), Quantitative, Pregnancy, Serum
Useful For
Early detection of pregnancy
Investigation of suspected ectopic pregnancy or other pregnancy-related complications
Monitoring in vitro fertilization patients
Method Name
Electrochemiluminescent Immunoassay
Reporting Name
HCG, Quantitative, Pregnancy, SSpecimen Type
SerumContainer/Tube:
Preferred: Serum gel
Acceptable: Red top
Specimen Volume: 0.5 mL
Collection Instructions:
1. Serum gel tubes should be centrifuged within 2 hours of collection.
2. Red-top tubes should be centrifuged and aliquoted within 2 hours of collection.
Additional Information: For use as a tumor marker (eg, testicular cancer patients), see BHCG / Beta-Human Chorionic Gonadotropin, Quantitative, Serum.
Specimen Minimum Volume
0.4 mL
Specimen Stability Information
| Specimen Type | Temperature | Time |
|---|---|---|
| Serum | Refrigerated (preferred) | 72 hours |
| Frozen | 365 days |
Clinical Information
Human chorionic gonadotropin (hCG) is a glycoprotein hormone that consists of 2 subunits (alpha and beta chains), which are associated to comprise the intact hormone. The alpha subunit is similar to those of luteinizing hormone, follicle-stimulating hormone, and thyroid-stimulating hormone. The beta subunit of hCG differs from other pituitary glycoprotein hormones, which results in its unique biochemical and immunological properties. This method quantitates the sum of intact hCG plus the beta subunit.
hCG is produced in the placenta during pregnancy. In nonpregnant women, it can also be produced by tumors of the trophoblast, germ cell tumors with trophoblastic components, and some nontrophoblastic tumors. The biological action of hCG serves to maintain the corpus luteum during pregnancy. It also influences steroid production. The serum in pregnant women contains mainly intact hCG. Measurement of the hCG concentration permits the diagnosis of pregnancy as early as 1 week after conception.
Reference Values
Negative: <5 IU/L
Indeterminate: 5-25 IU/L
Positive: >25 IU/L
Suggest repeat testing of indeterminate results in 72 hours.
Cautions
False-elevations (called phantom human chorionic gonadotropin: hCG) may occur with patients who have human antianimal or heterophilic antibodies.
Some specimens may not dilute linearly due to abnormal forms of hCG.
Elevated hCG concentrations not associated with pregnancy are found in patients with other diseases such as tumors of the germ cells, ovaries, bladder, pancreas, stomach, lungs, and liver. This test is not intended to detect or monitor tumors or gestational trophoblastic disease.
Day(s) Performed
Monday through Sunday; Continuously
Report Available
Same day/1 dayPerforming Laboratory
Mayo Medical Laboratories in Rochester
Test Classification
This test has been cleared or approved by the U.S. Food and Drug Administration and is used per manufacturer's instructions. Performance characteristics were verified by Mayo Clinic in a manner consistent with CLIA requirements.CPT Code Information
84702