These effects may also be involved in the observed reduction in NEC incidence in IGF-1 supplemented preterm pigs38 and for other possible effects on other organ systems, such as eyes (ROP) and lungs (BPD) in preterm infants.26,28 However, it is difficult to separate any direct immunomodulatory effects on such organs from IGF-1 related effects on tissue perfusion, vascularization and organ maturation.23 This evidence concerns the gene IGF1 and retinopathy of prematurity.