Growth Factor (IGF-1) Test - Insulin-Like Growth Factor-1 (IGF-1) Test

Insulin-like growth factor-1 (IGF-1), formerly known as somatomedin C, is a protein produced by liver cells in response to growth hormone (GH) stimulation. IGF-1 acts as a key mediator of many of GH's biological effects, including promoting growth and the development of bones and tissues. Unlike GH, which is released in pulses, IGF-1 blood levels remain relatively constant throughout the day, making it an excellent indicator of average GH production over the preceding 24 to 48 hours. It is often ordered alongside GH tests to evaluate pituitary disorders.