comparison of nutritional status between low birth weight and normal infants according to their growth in hospitals affiliated to isfahan university of medical sciences

background: about 21 millions premature and low birth weight (lbw) infants are born in the world every year where the majority of them are in the middle east countries. the literatures have shown that lbw infants and premature infants have a smaller chance to survive than the normal ones. this research carried out to determine the situation of catch up growth of lbw infants in comparison with normal ones. methods: a questionnaire was provided and completed for 3400 new born babies regarding different stages of study (at birth and three month, six months of age).they  included 214 lbw, 460 vlbw, and 38 elbw babies selected from alzahra and shahid beheshti hospitals. findings: 92% of normal babies had breast-feeding whereas 5% and 2%of them were fed by the gavage and  by bottle respectively. 50% of lbw were breast-fed. mean weight of normal babies were 3114 gr, whereas the mean weight of lbw, vlbw and elbw were 2058, 1348 and 953 gr, respectively . conclusion: it was concluded that the percentage of newborn babies using the gavage and breast-feeding increases as the birth weight decreases. there is a significant difference between the weight of new born babies in lbw, vlbw, elbw and normal ones at birth and one month, three month, six months of age (p < 0.0001).at six month of age the difference between weight of vlbw and elbw was not significant.