Insulin-like Growth Factor-binding Protein 3 (IGFBP-3)

What is Insulin-like Growth Factor-binding Protein 3?

The IGFBP-3 is a biological marker that help level up the human growth hormone in the blood. Its mode of action involves binding two hormones (IGF-1 and IGF-2) to their respective receptors in order to help with the production of the necessary hormone needed for a proper growth and development. When levels of the IGFBP-3 are low, a child may have short stature and a delayed growth. Low levels can also indicate problems in the pituitary and hypothalamus. When you have a low caloric intake and low protein intake, your levels tend to be lower.

According to a study published by the journal of molecular pathology, the IGFBP-3 is one of six different IGFBP’s hormones. These are proteins that help transport IGF’s and stabilize them in the bloodstream.

Why take the IGFBP-3 test?

This test is the perfect tool to diagnose growth disorders, as well as adult growth hormone deficiency. It is also used to monitor the recombinant human growth hormone treatment. Tested alongside the insulin-like growth factor-1 and growth hormone, it helps the diagnosis and follow up of both acromegaly and gigantism. If you are under a strict caloric diet that is low in proteins, you need to get tested for this hormone to assess your nutritional status.

What causes the levels of IGFBP-3 to rise?

Some medications may interfere with your levels of IGFBP-3. Biotin, also known as Vitamin B7, is a vitamin that is taken to improve hair, skin and nails. While a person needs around 30mcg per day, most supplements contain doses that are significantly higher than needed. Studies have shown these mega doses to interfere with the test results of numerous hormone tests like the IGFBP-3. This interference may lead to falsely high or low levels, causing misdiagnosis. Those who wish to get tested for the IGFBP-3 hormone need to stop taking their biotin supplements at least 72 hours prior to the test.

What do the IGFBP-3 test results mean?

Levels of this hormone change depending on both age and gender. These are the normal values ranges of men and women of different ages.

First, when taking a look at tanner stages, here are the values:

• For boys, normal values are between 1.4 and 5.2 mcg/ml for stage 1, between 2.3 and 6.3 mcg/ml for stage 2, between 3.1 and 8.9 mcg/ml for stage 3, between 3.7 and 8.7 mcg/ml for stage 4, and finally between 2.6 and 8.6 mcg/ml for stage 5.
• For girls, normal values are between 1.2 and 6.4 mcg/ml for stage 1, between 2.8 and 6.9 mcg/ml for stage 2, between 3.9 and 9.4 mcg/ml for stage 3, between 3.3 and 8.1 mcg/ml for stage 4, and finally between 2.7 and 9.1 mcg/ml for stage 5.

For adults, values are also different for every age group. These are the normal ranges for MEN:

• Between ages 1 and 7 days: less or equal to 0.7 mcg/ml
• Between ages 8 and 14 days: between 0.5 and 1.4 mcg/ml
• Between ages 15 days and 11 months: values are not available for this age group
• 1 year: between 1113 and 3180 mcg/l
• 2 years: between 1289 and 3634 mcg/l
• 3 years: between 1637 and 4492 mcg/l
• 4 years: between 1801 and 4878 mcg/l
• 5 years: between 1942 and 5193 mcg/l
• 6 years: between 2039 and 5384 mcg/l
• 7 years: between 2096 and 5466 mcg/l
• 8 years: between 2153 and 5550 mcg/l
• 9 years: between 2221 and 5660 mcg/l
• 10 years: between 2300 and 5801 mcg/l
• 11 years: between 2385 and 5956 mcg/l
• 12 years: between 2463 and 6093 mcg/l
• 13 years: between 2528 and 6198 mcg/l
• 14 years: between 2580 and 6272 mcg/l
• 15 years: between 2614 and 6306 mcg/l
• 16 years: between 2638 and 6316 mcg/l
• 17 years: between 2657 and 6319 mcg/l
• 18 years: between 2678 and 6327 mcg/l
• 19 years: between 2700 and 6341 mcg/l
• 20 years: between 2723 and 6361 mcg/l
• 21 to 25 years: between 2753 and 6361 mcg/l
• 26 to 30 years: between 2683 and 6127 mcg/l
• 31 to 35 years: between 2610 and 5977 mcg/l
• 36 to 40 years: between 2571 and 5982mcg/l
• 41 to 45 years: between 2515 and 6018 mcg/l
• 46 to 50 years: between 2374 and 5891 mcg/l
• 51 to 55 years: between 2251 and 5808 mcg/l
• 56 to 60 years: between 2133 and 5711 mcg/l
• 61 to 65 years: between 2027 and 5610 mcg/l
• 66 to 70 years: between 1926 and 5487 mcg/l
• 71 to 75 years: between 1779 and 5201 mcg/l
• 76 to 80 years: between 1673 and 5015 mcg/l
• 81 to 85 years: between 1632 and 5014 mcg/l
• 86 to 90 years: between 1665 and 5239 mcg/l

For WOMEN, normal IGFBP-3 values are as follows for every age group:

• 1 year: between 1221 and 3721 mcg/l
• 2 years: between 1388 and 4151 mcg/l
• 3 years: between 1553 and 4557 mcg/l
• 4 years: between 1713 and 4933 mcg/l
• 5 years: between 1854 and 5242 mcg/l
• 6 years: between 1945 and 5403 mcg/l
• 7 years: between 2019 and 5515 mcg/l
• 8 years: between 2096 and 5629 mcg/l
• 9 years: between 2180 and 5762 mcg/l
• 10 years: between 2270 and 5908 mcg/l
• 11 years: between 2360 and 6055 mcg/l
• 12 years: between 2444 and 6184 mcg/l
• 13 years: between 2517 and 6286 mcg/l
• 14 years: between 2580 and 6365 mcg/l
• 15 years: between 2636 and 6428 mcg/l
• 16 years: between 2682 and 6470 mcg/l
• 17 years: between 2718 and 6495 mcg/l
• 18 years: between 2749 and 6510 mcg/l
• 19 years: between 2779 and 6527 mcg/l
• 20 years: between 2809 and 6550 mcg/l
• 21 to 25 years: between 2855 and 6559 mcg/l
• 26 to 30 years: between 2752 and 6219 mcg/l
• 31 to 35 years: between 2573 and 5804 mcg/l
• 36 to 40 years: between 2504 and 5709mcg/l
• 41 to 45 years: between 2409 and 5610 mcg/l
• 46 to 50 years: between 2343 and 5612 mcg/l
• 51 to 55 years: between 2306 and 5703 mcg/l
• 56 to 60 years: between 2238 and 5717 mcg/l
• 61 to 65 years: between 2161 and 5691 mcg/l
• 66 to 70 years: between 2059 and 5572 mcg/l
• 71 to 75 years: between 2005 and 5549 mcg/l
• 76 to 80 years: between 1950 and 5490 mcg/l
• 81 to 85 years: between 1925 and 5498 mcg/l
• 86 to 90 years: between 1961 and 5672 mcg/l

When the levels are below normal ranges, this indicates a possible GH deficiency, growth hormone resistance, chronic malnutrition, liver failure or diabetes. High levels of IGFBP-3 may, on the other hand, indicate an overproduction of growth hormone, chronic renal failure, acromegaly or gigantism. It is important to keep in mind that liver diseases may lead to discrepancies in this hormone’s levels.

Where can I get an IGFBP-3 test near me?

Please use our Lab Locator to find find a convenient testing location.

Reviewed By: Dr. Kurt Kloss, MD
Last Reviewed Date: Mar 12, 2020