IGF 1 LR3 does not promote growth in late gestation growth restricted fetal sheep American Journal of Physiology Endocrinology and Metabolism American Physiological Society IGF 1 LR3 The Muscle Building Peptide Everyone's Talking About IGF 1 LR3 is one of the most powerful performance peptides used for muscle growth, recovery, and fat loss. It's a modified version Recombinant Human LR3 IGF I IGF 1 GMP Protein, CF 8335D GMP: R&D Systems IGF 1 infusion to fetal sheep increases organ growth but not by stimulating nutrient transfer to the fetus American Journal of Physiology Endocrinology and Metabolism American Physiological Society