 Enteral nutrition of preterm and intrauterine growth-restricted IUGR infants is still a challenge for neonatologists. Due to the immaturity of the gastrointestinal tract, preterm infants are at high risk of developing feeding intolerance FI or necrotizing enterocolitis NEC, which is the most feared gastrointestinal complication of prematurity. The occurrence of FI often prompts clinicians to withhold, decrease or discontinue enteral feeds; thus, the establishment of an adequate early enteral nutrition is frequently hampered. Early identification of preterm infants at high risk for gastrointestinal complications could help clinical decisions on the introduction and the advancement of enteral feeding. 