An Insulin-like Growth Factor Test, or IGF-1 Blood Test, is ordered to help diagnose the cause of growth abnormalities and to assess pituitary function.The IGF-1 Blood Test is also known as SM-C/IGF-1, Somatomedin-C, and Sulfation Factor. No fasting is required for this test, and results will be delivered within 1-2 days. For patients without insurance, this test is a convenient, low-cost alternative to a traditional doctor’s office visit.An IGF-1 Blood Test is commonly ordered for patients who have symptoms that indicate insufficient or excess production of human growth hormone (HGH) and IGF-1.Such symptoms include gigantism or slow or delayed growth and development in children, and acromegaly or decreased bone density and muscle strength in adults. The test is also used if an underactive pituitary gland is suspected or to monitor patients on HGH therapy.IGF-1 is a polypeptide hormone produced in the liver and skeletal muscles in response to HGH stimulation. IGF-1, which mediates the actions of HGH and mirrors an excess or deficiency, is essential for normal growth and development of bone and tissue. Unlike HGH, IGF-1 levels are stable throughout the day, making it a useful indicator of average HGH levels.The IGF-1 Blood Test does not diagnose HGH deficiency. Patients may wish to order this test in addition to the HGH Serum Test to provide more information. To diagnose hypopituitarism, the IGF-1 Blood Test may be ordered alongside other pituitary hormone tests, such as the Adrenocoticotropic Hormone (ACTH) Plasma Test, also known as a Cortisol Blood Test.