Complete Blood Count (CBC) Test: What It Is, Why It's Done, and How to Prepare
A blood test that measures androstenedione levels 1.5 hours after a hormone stimulation challenge to evaluate adrenal gland function.
{"Measures how your adrenal glands respond to a stimulation challenge","Helps diagnose conditions like congenital adrenal hyperplasia or adrenal tumors","Blood sample is taken before and 1.5 hours after the challenge","The test evaluates androgen hormone production from the adrenal glands"}
Key facts at a glance
- LOINC
- 58919-2
- Short code
- ANDRO15
- Synonyms
- Androst 1.5h p chal SerPl-mCnc
- Category
- chemistry
- Sample
- serum
- Container
- Red-top serum tube or serum separator tube (SST)
- Units
- N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- ≥ 0 years
- Method
- Immunoassay (Chemiluminescent or Radioimmunoassay)
- CPT
- 82157
- SNOMED
- 165407009
- Specimen volume
- 1.0 mL serum minimum (2.0 mL preferred for dynamic testing protocols)
- Stability
- Serum stable for 24 hours at room temperature, 7 days at 2-8°C, and up to 30 days at -20°C. Avoid repeated freeze-thaw cycles.
- Hemolysis max
- 100
- Lipemia max
- 500
- Icterus max
- 20
- TAT
- 24–72 hours
- Order
- routine
A complete blood count (CBC) is a common blood test that measures the different cells in your blood, including red blood cells, white blood cells, and platelets, giving your provider a broad picture of your overall health.
The Androstenedione Challenge Test is a blood test that measures the level of androstenedione, a hormone produced by the adrenal glands, in your blood. Androstenedione is an androgen (male sex hormone) that plays a role in the development of male characteristics and is also a precursor to other hormones like testosterone and estrogen. This test is performed after a stimulation challenge—typically involving a medication that stimulates the adrenal glands—to see how well they respond and produce androstenedione.
Your doctor may order a CBC as part of a routine checkup or to help diagnose conditions such as anemia, infection, inflammation, or blood disorders, and to monitor how a treatment or medication is working over time.
Your healthcare provider may order this test if you have symptoms suggesting a problem with your adrenal glands, such as abnormal hair growth, early puberty, menstrual irregularities, or signs of hormonal imbalances. The test helps doctors determine if your adrenal glands are functioning properly and can identify conditions that affect hormone production.
A health care professional will clean your skin and draw a small sample of blood, usually from a vein in your arm, using a thin needle. The sample is sent to a laboratory, and results are often ready within one to two days.
The test involves two blood draws: a baseline sample taken before the challenge, and a second sample taken 1.5 hours after receiving a stimulating medication (usually administered as an injection). The medication triggers your adrenal glands to produce hormones, and the test measures how much androstenedione is produced in response. The entire procedure typically takes about 2-3 hours.
Most people need no special preparation for a CBC, so you can usually eat and drink normally unless your provider asks you to fast for other tests done at the same time. Drink water beforehand, and tell your care team about any medicines or supplements you take.
Follow your healthcare provider's instructions carefully. You may need to fast (not eat or drink except water) for a certain period before the test. Inform your doctor about all medications you are taking, as some drugs can affect hormone levels. Certain medications, especially steroids or hormonal treatments, may need to be paused before the test. Wear comfortable clothing with sleeves that can be easily rolled up for the blood draws.
Reference range
Reference values vary by laboratory, assay methodology, age, sex, and the specific challenge protocol used. Values must be interpreted in context of baseline (pre-challenge) and 1.5-hour post-challenge measurements.N/A
No fasting required. Patient should be instructed on the specific challenge protocol (e.g., ACTH stimulation, GnRH stimulation, or other dynamic endocrine testing) as ordered by the physician. Specimen should be collected exactly 1.5 hours (90 minutes) post-challenge agent administration.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
Abnormal androstenedione levels after a challenge can indicate various conditions. Elevated levels may suggest congenital adrenal hyperplasia (a genetic disorder affecting adrenal hormone production), adrenal tumors, or polycystic ovary syndrome (PCOS). Low levels might indicate adrenal insufficiency (Addison's disease) or pituitary gland problems. The results help your healthcare provider diagnose the cause of hormonal symptoms and guide appropriate treatment. Your doctor will interpret the results alongside your symptoms, other test results, and clinical history.
Frequently asked questions
Is the androstenedione challenge test safe?
How long does it take to get results?
What do abnormal results mean?
Will I need to repeat the test?
Sources
- 1
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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.
If you think you may have a medical emergency, call your local emergency number or go to the nearest emergency department immediately.
Medically reviewed by WellAlly Editorial Team Last reviewed August 15, 2026. · Read our editorial policy