Growth hormone Health Article

Definition

The growth hormone test measures the amount of growth hormone in the blood.

Alternative Names

GH

How the test is performed

Blood is typically drawn from a vein, usually from the inside of the elbow or the back of the hand. The site is cleaned with germ-killing medicine (antiseptic). The health care provider wraps an elastic band around the upper arm to apply pressure to the area and make the vein swell with blood.

Next, the health care provider gently inserts a needle into the vein. The blood collects into an airtight vial or tube attached to the needle. The elastic band is removed from your arm. Once the blood has been collected, the needle is removed, and the puncture site is covered to stop any bleeding.

In infants or young children, a sharp tool called a lancet may be used to puncture the skin and make it bleed. The blood collects into a small glass tube called a pipette, or onto a slide or test strip. A bandage may be placed over the area if there is any bleeding.

How to prepare for the test

There is no special preparation.

How the test will feel

When the needle is inserted to draw blood, some people feel moderate pain, while others feel only a prick or stinging sensation. Afterward, there may be some throbbing.

Why the test is performed

Growth hormone may be measured when adults or children are not growing normally, or when there is a history of a pituitary gland problem.

Growth hormone is released from the anterior pituitary gland. Too much growth hormone can cause abnormal growth patterns called acromegaly in adults and gigantism in children.

Too little growth hormone can cause short stature in children, and changes in muscle mass, cholesterol levels, and bone strength in adults.

Normal Values

The normal range is 0 - 3 ng/mL.

GH is released in pulses, so a higher level may be normal if the blood was drawn during a pulse.

Note: ng/mL = nanograms per milliliter

Normal value ranges may vary slightly among different laboratories. Talk to your doctor about the meaning of your specific test results.