IGF Binding Protein-3 (IGFBP-3)

Catalog information reviewed: August 24, 2026 by the Sunridge Medical clinical team.

What this laboratory test evaluates

DetailsIGF Binding Protein-3 (IGFBP-3) – Insulin-like growth factor binding proteins bind IGF-I and IGF-II with high affinity but do not bind insulin. Of the 6 distinct IGF binding proteins structurally characterized at this time, IGFBP-3 has been shown to be the major carrier of the IGFs, transporting approximately 95% of circulating IGF-I and IGF-II.

IGFBP-3 is growth hormone (GH) responsive. Thus, levels are high in acromegaly and low in hypopituitarism, and levels increase in GH-deficient children after GH administration. Other causes of short stature that result in reduced IGFBP-3 levels include poorly controlled diabetes. The IGFBP-3 assay is useful in assessing nutritional status, since IGFBP-3 decreases during both caloric and protein restriction.

What type of sample is required for this test?1 mL serum

Test ResourcesFor more information, please consult your healthcare provider.

Additional test information

IGF Binding Protein-3 (IGFBP-3) – Insulin-like growth factor binding proteins bind IGF-I and IGF-II with high affinity but do not bind insulin. Of the 6 distinct IGF binding proteins structurally characterized at this time, IGFBP-3 has been shown to be the major carrier of the IGFs, transporting approximately 95% of circulating IGF-I and IGF-II. IGFBP-3 is growth hormone (GH) responsive. Thus, levels are high in acromegaly and low in hypopituitarism, and levels increase in GH-deficient children after GH administration. Other causes of short stature that result in reduced IGFBP-3 levels include poorly controlled diabetes. The IGFBP-3 assay is useful in assessing nutritional status, since IGFBP-3 decreases during both caloric and protein restriction.

Collection and processing

• Sample type: Serum
• Fasting: No
• Estimated laboratory processing: Results should be available in 2 – 5 business days after the sample is collected

How Sunridge uses laboratory information

Sunridge considers the medical question, symptoms, history, medications, prior results, and whether the finding could change care before recommending testing. A laboratory result is not interpreted in isolation and does not establish a diagnosis by itself.

Before requesting this test

Availability, collection requirements, eligibility, and processing estimates can change. Sunridge reviews each request and, when appropriate, creates the order through Fullscript. Follow the current instructions supplied with the approved order.