The Retinopathy of Prematurity (ROP)(ROP) was described for the first time in 1942 (4), at the present moment it is a public health problem in the developing countries. Of each 100.000 blind child in Latin America, 24.000 are due to ROP (240/1000 blind child) (17). It is the main cause of blindness in premature new born (1,4,5). It is of multifactorial etiology (17) but it has been related to a short gestational age (smaller to 32 weeks of gestation) (4), to low birth weight (less of 1500gr) or very low birth weight (less 1250gr)(1,4,5,17,18,20), to the administration of high oxygen concentration immediately after birth (1,3,18), low levels of the Insulin-like growth factor(IGF-I) and excessive production of VEGF (3,17).