Insulin-like growth factor I (IGF-I) had been shown to play a role in the patho-physiology of Retinopathy of prematurity (ROP) which may develop during the early weeks after preterm birth. A deficit of IGF-I in the first few weeks of post-natal life is a possible diagnostic marker for Retinopathy of prematurity. Methods: Measuring serum IGF-I at 1st and 30th day of 74 infant with Gestational age (mean) 31.76±2.22 weeks (preterm cases group) and 20 full term infant with Gestational age (mean) 38.05±1.15 weeks (control group). All infants had Ophthalmic Fundus examination at 30th day of life. Results: Five babies had developed ROP, their gestational age (mean) 29.6±0.89 weeks. Sixty nine babies had gestational age (mean) 31.91±2.21weeks had not develope ROP. Mean serum IGF-I level in preterm group was statistically significantly lower than that of control group .We found that the cut off points of IGF-1 between the ROP and non-ROP neonates preterm group are 27ng/ml. A significant association was found between the development of retinopathy and other variables as early gestational age, low birth weight, prolonged mechanical ventilation, sepsis and low levels of serum IGF-I in the fourth week. Conclusions: These results indicate that persistent low serum concentrations of IGF-I after premature birth are associated with later development of ROP and other complications of prematurity.
