Test Catalog

Test Id : HGH

Growth Hormone, Serum

Useful For
Suggests clinical disorders or settings where the test may be helpful

Diagnosis of acromegaly and assessment of treatment efficacy when interpreted in conjunction with results from glucose suppression test


Diagnosis of human growth hormone deficiency when interpreted in conjunction with results from growth hormone stimulation test


This test is not intended for use as a screen for acromegaly.


This test has limited value in assessing growth hormone secretion in normal children.

Method Name
A short description of the method used to perform the test

Immunoenzymatic Assay

NY State Available
Indicates the status of NY State approval and if the test is orderable for NY State clients.


Reporting Name
Lists a shorter or abbreviated version of the Published Name for a test

Growth Hormone, S

Lists additional common names for a test, as an aid in searching

Growth Hormone Provocative Test

Growth Hormone Stimulation

hGH (Human Growth Hormone)

Human Growth Hormone

Somatotrophic Hormone


Specimen Type
Describes the specimen type validated for testing


Ordering Guidance

The recommended test for assessing growth hormone secretion in normal children is IGF1I / Insulin-Like Growth Factor 1, Serum.


The preferred test for acromegaly screening is IGF1 / Insulin-Like Growth Factor 1, Serum.

Specimen Required
Defines the optimal specimen required to perform the test and the preferred volume to complete testing

Patient Preparation: Fasting, 8 hours

Collection Container/Tube: 

Preferred: Serum gel 

Acceptable: Red top 

Submission Container/Tube: Plastic vial 

Specimen Volume: 0.6 mL 

Collection Instructions:

1. If multiple specimens are collected, submit each vial under a separate order. 

2. Label specimens appropriately with the corresponding collection times. 


Specimen Minimum Volume
Defines the amount of sample necessary to provide a clinically relevant result as determined by the Testing Laboratory

0.5 mL

Reject Due To
Identifies specimen types and conditions that may cause the specimen to be rejected

Gross hemolysis Reject
Gross lipemia OK

Specimen Stability Information
Provides a description of the temperatures required to transport a specimen to the performing laboratory, alternate acceptable temperatures are also included

Specimen Type Temperature Time Special Container
Serum Refrigerated (preferred) 7 days
Frozen 90 days

Useful For
Suggests clinical disorders or settings where the test may be helpful

Diagnosis of acromegaly and assessment of treatment efficacy when interpreted in conjunction with results from glucose suppression test


Diagnosis of human growth hormone deficiency when interpreted in conjunction with results from growth hormone stimulation test


This test is not intended for use as a screen for acromegaly.


This test has limited value in assessing growth hormone secretion in normal children.

Clinical Information
Discusses physiology, pathophysiology, and general clinical aspects, as they relate to a laboratory test

The anterior pituitary secretes human growth hormone (hGH) in response to exercise, deep sleep, hypoglycemia, and protein ingestion. hGH stimulates hepatic insulin-like growth factor-1 and mobilizes fatty acids from fat deposits to the liver. Hyposecretion of hGH causes dwarfism in children. Hypersecretion causes gigantism in children or acromegaly in adults.


Because hGH levels in normal and diseased populations overlap, hGH suppression and stimulation tests are needed to evaluate conditions of hGH excess and deficiency; random hGH levels are inadequate.

Reference Values
Describes reference intervals and additional information for interpretation of test results. May include intervals based on age and sex when appropriate. Intervals are Mayo-derived, unless otherwise designated. If an interpretive report is provided, the reference value field will state this.


Males: 0.01-0.97 ng/mL

Females: 0.01-3.61 ng/mL

Reference intervals have not been formally verified in-house for pediatric and adolescent patients. The published literature indicates that reference intervals for adult, pediatric, and adolescent patients are comparable.


For SI unit Reference Values, see https://www.mayocliniclabs.com/order-tests/si-unit-conversion.html

Provides information to assist in interpretation of the test results

Acromegaly: For suppression testing, normal subjects have a nadir human growth hormone (hGH) concentration  below 0.3 ng/mL after ingestion of a 75-gram glucose dose. Patients with acromegaly fail to show normal suppression. Using the Access ultrasensitive hGH assay, a cutoff of 0.53 ng/mL for nadir hGH was found to most accurately differentiate patients with acromegaly in remission from active disease with a sensitivity of 97% (95% CI, 83%-100%) and a specificity of 100% (95% CI, 82%-100%).(1)


Deficiency: A normal response following stimulation tests is a peak hGH concentration above 5 ng/mL in children and above 4 ng/mL in adults. For children, some experts consider hGH values between 5 ng/mL and 8 ng/mL equivocal and only GH peak values greater than8 ng/mL as truly normal. Low levels, particularly under stimulation, indicate hGH deficiency.

Discusses conditions that may cause diagnostic confusion, including improper specimen collection and handling, inappropriate test selection, and interfering substances

As the hGH test has limited value in assessing growth hormone secretion in normal children, IGF1I / Insulin-Like Growth Factor 1, Serum is recommended as the first test for assessing deficient or excess growth during childhood and adolescent development. IGF1 reference intervals for Tanner stages are available. Suspected causes of dwarfism should be diagnosed with the aid of provocative testing.


Elevated levels of human growth hormone indicate the possibility of gigantism or acromegaly, but must be confirmed with stimulation and suppression testing.


Growth hormone is secreted in surges; single measurements are of limited diagnostic value.

Clinical Reference
Recommendations for in-depth reading of a clinical nature

1. Bancos I, Algeciras-Schimnich A, Woodmansee WW, et al: Determination of nadir growth hormone concentration cutoff following oral glucose tolerance testing using the Beckman Coulter ultrasensitive growth hormone assay patients with newly diagnosed acromegaly, acromegaly in remission, and healthy subjects. Endocr Pract 2013 Jun 27:1-26

2. Camacho-Hubner C: Assessment of growth hormone status in acromegaly: what biochemical markers to measure and how? Growth Hormone IGF Res 2000;10 Suppl B:S125-299

3. Nilsson AG: Effects of growth hormone replacement therapy on bone markers and bone mineral density in growth hormone-deficient adults. Horm Res 2000;54 Suppl 1:52-57

4. Strasburger CJ, Dattani MT: New growth hormone assays: potential benefits. Acta Paediatr 1997 Nov;Suppl 423:5-11

5. Okada S, Kopchick JJ: Biological effects of growth hormone and its antagonist. Trends Mol Med 2001Mar;7:126-132

6. Veldhuis JD, Iranmanesh A: Physiological regulation of human growth hormone (GH)-insulin-like growth factor type I (IGF-I) axis: predominant impact of age, obesity, gonadal function, and sleep. Sleep 1996;19:S221-224

7. Melmed S: Pathogenesis and diagnosis of growth hormone deficiency in adults. N Engl J Med 2019 Jun 27;380(26):2551-2562. doi: 10.1056/NEJMra1817346

Method Description
Describes how the test is performed and provides a method-specific reference

The instrument used is the Beckman Coulter UniCel DXI 800. The Access Ultrasensitive human growth hormone (hGH) assay is a simultaneous one-step immunoenzymatic ("sandwich") assay. A sample is added to a reaction vessel along with polyclonal goat anti-hGH alkaline phosphatase conjugate and paramagnetic particles coated with mouse monoclonal anti-hGH antibody. The patient sample hGH binds to the monoclonal anti-hGH on the solid phase, while the goat anti-hGH-alkaline phosphatase conjugate reacts with a different antigenic site on patient sample hGH. After incubation in a reaction vessel, materials bound to the solid phase are held in a magnetic field while unbound materials are washed away. Then, the chemiluminescent substrate Lumi-Phos 530 is added to the vessel and light generated by the reaction is measured with a luminometer. The light production is directly proportional to the concentration of hGH in the sample. The amount of analyte in the sample is determined from a stored, multi-point calibration curve.(Package insert: Beckman Coulter Inc, Fullerton, CA, 03/2019)

PDF Report
Indicates whether the report includes an additional document with charts, images or other enriched information


Day(s) Performed
Outlines the days the test is performed. This field reflects the day that the sample must be in the testing laboratory to begin the testing process and includes any specimen preparation and processing time before the test is performed. Some tests are listed as continuously performed, which means that assays are performed multiple times during the day.

Monday through Friday

Report Available
The interval of time (receipt of sample at Mayo Clinic Laboratories to results available) taking into account standard setup days and weekends. The first day is the time that it typically takes for a result to be available. The last day is the time it might take, accounting for any necessary repeated testing.

1 to 3 days

Specimen Retention Time
Outlines the length of time after testing that a specimen is kept in the laboratory before it is discarded

14 days

Performing Laboratory Location
Indicates the location of the laboratory that performs the test


Several factors determine the fee charged to perform a test. Contact your U.S. or International Regional Manager for information about establishing a fee schedule or to learn more about resources to optimize test selection.

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  • Prospective clients should contact their Regional Manager. For assistance, contact Customer Service.

Test Classification
Provides information regarding the medical device classification for laboratory test kits and reagents. Tests may be classified as cleared or approved by the US Food and Drug Administration (FDA) and used per manufacturer instructions, or as products that do not undergo full FDA review and approval, and are then labeled as an Analyte Specific Reagent (ASR) product.

This test has been cleared, approved, or is exempt by the US 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
Provides guidance in determining the appropriate Current Procedural Terminology (CPT) code(s) information for each test or profile. The listed CPT codes reflect Mayo Clinic Laboratories interpretation of CPT coding requirements. It is the responsibility of each laboratory to determine correct CPT codes to use for billing.

CPT codes are provided by the performing laboratory.


LOINC® Information
Provides guidance in determining the Logical Observation Identifiers Names and Codes (LOINC) values for the order and results codes of this test. LOINC values are provided by the performing laboratory.

Test Id Test Order Name Order LOINC Value
HGH Growth Hormone, S 2963-7
Result Id Test Result Name Result LOINC Value
Applies only to results expressed in units of measure originally reported by the performing laboratory. These values do not apply to results that are converted to other units of measure.
HGH Growth Hormone, S 2963-7

Test Setup Resources

Setup Files
Test setup information contains test file definition details to support order and result interfacing between Mayo Clinic Laboratories and your Laboratory Information System.

Excel | Pdf

Sample Reports
Normal and Abnormal sample reports are provided as references for report appearance.

Normal Reports | Abnormal Reports

SI Sample Reports
International System (SI) of Unit reports are provided for a limited number of tests. These reports are intended for international account use and are only available through MayoLINK accounts that have been defined to receive them.

SI Normal Reports | SI Abnormal Reports