Because prematurity is one of the factors that contributes to ROP and the IGF-I level is determined by the IGF-I receptor (IGF-I R) and the most prevalent polymorphism of IGF-I R (3174 G to A) exhibited low levels of free plasma IGF-I, it is possible that it may have a role in ROP. Here, IGF1R is linked to retinopathy of prematurity.