Lab test
Growth Hormone Level Test – GH Blood Test
Growth Hormone Level Test – GH Blood Test can be ordered without a referral from your own doctor, and this guide covers what to expect. A growth hormone level test measures the amount of human growth hormone in the blood. It helps evaluate conditions related to growth hormone deficiency or excess.
Lab requirements in Growth Hormone Level Test – GH Blood Test
Here is what you need before ordering and completing the Growth Hormone Level Test – GH Blood Test. Review each item and confirm the details with the collection lab.
- Physician's order
- Included. A physician's order is required for lab testing and is provided for you by our partner's physicians — no referral from your own doctor is needed.
- Fasting
- Fasting is required for this test — follow the collection lab's instructions.
- Preparation
- Preparation instructions can vary depending on the specific reason for testing and the laboratory performing the analysis. Always follow the collection lab's directions regarding fasting…
- Sample & visit
- A blood and/or urine sample is collected; the visit usually takes about 10 minutes.
- Identification
- Bring the lab requisition form from your account. The collection lab may also ask for a government-issued photo ID.
- Turnaround
- 1-3 business days
- Availability
- Our partner lab does not serve ND, RI, NY, NJ, MD or HI. Confirm availability for your location with the collection lab.
Before you go
- Order your test before visiting a lab, then use the requisition form in your account.
- Print the requisition form, or fax it to the lab directly from your account.
- No scheduling is needed — visit the collection lab during its normal business hours.
- A blood and/or urine sample is collected; the visit usually takes about 10 minutes.
- Bring a government-issued photo ID in case the lab requests it.
- Results are posted to your secure account within 1–3 business days.
Requirements are summarized from our partner lab's published policies. Preparation and availability can change — confirm current instructions with the collection lab before your visit.
What this test is
This blood test quantifies the concentration of growth hormone, a hormone produced by the pituitary gland that regulates growth, metabolism, and muscle and bone health. Because growth hormone is released in pulses, a single measurement may be interpreted alongside other tests or dynamic stimulation/suppression procedures.
What it measures
- Growth hormone (GH) — Reflects the amount of human growth hormone circulating in the blood at the time of collection.
What the test involves
The test requires a standard blood draw from a vein in your arm, usually collected at a laboratory or clinic. In some cases, multiple samples may be taken over a period of time to account for the hormone's natural fluctuations.
Why it is often ordered
A clinician may order this test to investigate symptoms of growth hormone deficiency, such as delayed growth in children or changes in body composition in adults. It can also be used to evaluate suspected excess growth hormone production, which may cause conditions like acromegaly or gigantism.
Preparation
Preparation instructions can vary depending on the specific reason for testing and the laboratory performing the analysis. Always follow the collection lab's directions regarding fasting, timing, and any medications.
How results are reported
Results are typically reported as a numerical value in nanograms per milliliter (ng/mL) or micrograms per liter (mcg/L). Reference ranges differ between laboratories and may depend on age, sex, and the time of day the sample was collected, so your clinician will interpret your result in context.
Before you go
- Whether fasting is required before the blood draw
- Any medications or supplements that might affect growth hormone levels
- The best time of day to schedule the collection
FAQ
Frequently asked questions
Do I need to fast before a growth hormone level test?
Fasting requirements depend on the specific test protocol and the laboratory's instructions. Some growth hormone tests are done after an overnight fast, while others may not require fasting. Always confirm with the collection lab before your appointment.
Can a single growth hormone test diagnose a deficiency or excess?
A single growth hormone measurement is often not enough on its own because levels fluctuate throughout the day. Clinicians may combine it with other tests, such as stimulation or suppression tests, and consider symptoms and other hormone levels to make a diagnosis.
What factors can affect my growth hormone test results?
Growth hormone levels can be influenced by sleep, stress, exercise, diet, medications, and the time of day the sample is taken. Your age and sex also play a role. These factors are why reference ranges are specific to each laboratory and testing context.
How long does it take to get growth hormone test results?
Turnaround time is typically a few business days, but it can vary by laboratory and the complexity of the testing. Your healthcare provider will receive the results and discuss them with you.
Related
Related tests
Locations
Order Growth Hormone Level Test – GH Blood Test by state
Choose a state for local context.