GROWTH HORMONE STIMULATION TEST

Growth Hormone Stimulation Test Overview

Growth hormone (GH) stimulation tests are blood tests that help to check whether your body is producing a normal level of GH. GH, also known as human growth hormone, plays a vital role in overall growth and supports metabolism—the process by which the body converts food into energy. If you or your child shows signs of a GH imbalance, your doctor may recommend a growth hormone stimulation test. 

In some cases, particularly in children, the condition can improve naturally over time. With a growth hormone stimulation test, doctors can offer you the right medication needed to achieve better results.

Why is the Growth Hormone Stimulation Test Prescribed?

In adults, low levels of growth hormone can lead to symptoms such as fatigue, increased fat storage, low bone density, and an overall decline in quality of life. In many cases, these signs often resemble those of other medical conditions, which is why doctors recommend undergoing a Growth Hormone Stimulation Test.

Growth hormone tests help identify and monitor different GH-related disorders, including:

• Growth Hormone Deficiency: This happens when the body fails to produce enough GH. In children, this can slow down normal growth and cause them to be significantly shorter than peers of the same age and sex. In adults, GH deficiency is often linked to reduced muscle strength and low bone density.

• Acromegaly: A disorder in adults caused by excess GH production. It typically results in enlarged hands, feet, and facial features, as well as abnormally thickened bones.

Components of Growth Hormone Stimulation Test

There are two different results of the growth hormone stimulation test.

Normal Result

Normal peak value, at least 10 ng/mL (10 µg/L)

Indeterminate, 5 to 10 ng/mL (5 to 10 µg/L)

Subnormal, 5 ng/mL (5 µg/L)

A normal result rules out the hGH deficiency.

If the test does not show an increase in GH levels, it suggests that the anterior pituitary has a limited reserve of human growth hormone (hGH).

In children, this indicates a growth hormone deficiency, while in adults, it may point to adult-onset GH deficiency.

Preparation and Perquisites

The overall growth hormone test procedure is quite fast. The clinician would withdraw a blood sample from a vein for testing purposes. Besides, there are other aspects -

• Fasting: Patients are generally asked to fast for 8–12 hours before the test.

• Medication: It’s important to inform the doctor about all current medications.

• Health Condition: The test should be avoided during periods of acute illness, since being unwell can affect growth hormone secretion.