The growth hormone (GH) blood test measures levels of human growth hormone and IGF-1 (insulin-like growth factor 1) to screen for growth disorders and pituitary gland dysfunction. This lab test helps diagnose growth hormone deficiency in adults.
What Does the GH Blood Test Measure?
Growth hormone stimulates tissue growth, cell reproduction and regeneration. This test checks levels of GH and IGF-1 to evaluate the function of the pituitary gland, which produces GH.
- GH level – Growth hormone circulates in the blood in pulses and is normally found in very low amounts. A low GH indicates the pituitary is not making enough.
- IGF-1 level – This growth factor is produced by the liver in response to GH. Low IGF-1 correlates to inadequate GH secretion.
Testing both GH and IGF-1 provides the most complete screening for possible growth hormone deficiency.
Who Should Have Growth Hormone Testing?
GH testing may be recommended for:
- Adults with fatigue, decreased muscle mass and other symptoms of adult GH deficiency
- Diagnosing the cause of pituitary disorders like tumors
- Monitoring GH treatment
GH stimuation testing may also be done to confirm GH deficiency.
Preparing for a Growth Hormone Blood Test
No special preparation is required. GH levels can fluctuate so blood may be drawn at multiple times during the day. Food intake and sleep can impact results. Your doctor may have you fast overnight prior to testing. Certain medications may also affect GH levels.
Understanding Test Results
Normal ranges vary depending on age, sex and lab methods. Generally, normal results are:
- GH – Below 10 ng/mL for adults and under 7 ng/mL for children
- IGF-1 – Between 117-329 ng/mL for adults
An endocrinologist will interpret your GH and IGF-1 levels based on your symptoms and medical history. Further testing may be needed to confirm a growth hormone deficiency before starting treatment.
Accessing GH Testing Near Me
Our extensive lab network provides convenient access to growth hormone testing across the U.S. Order your test online and get same-day GH blood draw at one of 4,000+ locations. We work with top national labs like Quest Diagnostics and Labcorp to make testing convenient . Results delivered through our secure patient portal.
Insulin-Like Growth Factor I (IGF-I) (16293)
Testosterone, free and total (36170)
Testosterone, free and total (081786)
Growth Hormone, Serum (004275)
Estimated Turn Around For Results:
2-10 Business Days
For an exact turnaround time for results, please contact us at Personalabs and we will contact the lab on your behalf as turnaround times vary depending on testing location or lab testing provider.