Alpha Subunit of Human Chorionic Gonadotropin, Serum/Plasma — Mass Concentration
Measures the amount of the alpha subunit of human chorionic gonadotropin in blood. This test is distinct from the intact hCG measurement commonly used in pregnancy testing.
["This blood test measures an alpha-hCG subunit and is interpreted along with other hCG tests and the clinical situation."]
Key facts at a glance
- LOINC
- 27252-6
- Short code
- A-HCG SerPl-mCnc
- Synonyms
- A-HCG SerPl-mCnc
- Category
- liver
- Sample
- serum
- Container
- Red-top tube (SST)
- Units
- N/A
- Ref low
- 0
- Ref high
- 5
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- CPT
- 84702
- SNOMED
- 275917004
- Specimen volume
- 5 mL
- Stability
- Room temperature: 4h, Refrigerated: 24h, Frozen: 7d
- Hemolysis max
- 500
- Lipemia max
- 1000
- Icterus max
- 500
- TAT
- 4–24 hours
- Order
- routine
What is this test?
This test measures the concentration of the alpha subunit of human chorionic gonadotropin, or hCG, in serum or plasma. hCG is a hormone associated with pregnancy and is also produced by certain other tissues and tumors.
Why might I need this test?
A clinician may order it when evaluating or monitoring pregnancy, gestational trophoblastic disease, or certain tumors that produce hCG. It may be used alongside intact or total hCG measurements rather than as a stand-alone test.
How is the test performed?
A blood sample is collected by venipuncture, and the serum or plasma is analyzed in the laboratory to determine the concentration of the alpha hCG subunit. The result is usually reported as an amount per unit of blood volume.
How do I prepare for the test?
Fasting is generally not required, but follow any instructions from your clinician. Tell the laboratory if you are pregnant, recently pregnant, or have received an hCG injection, because these factors can affect the results and their interpretation.
Reference range
Non-pregnant: <5 mIU/mLN/A
No special preparation usually required. Stay well hydrated. Inform your healthcare provider of all medications and supplements you are taking.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
◆Associated findings1
Short name
Alpha hCG subunit
Frequently asked questions
Is this the same as a standard pregnancy hCG test?
Can a home pregnancy test determine the alpha hCG subunit?
Do I need to fast before this blood test?
Sources
- 1
- 2Lab Tests OnlineSource
- 3
Click any link to access the full source. PubMed Central (PMC) links provide free full-text access.
This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.
This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.
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Medically reviewed by WellAlly Editorial Team Last reviewed August 16, 2026. · Read our editorial policy