We aimed to investigate the role of hypoxia-ischemia in the pathophysiology of early NEC/NEC like disease (ENEC) and classic NEC/NEC like disease (CNEC) in preterm infants. In this pilot study, preterm infants who developed the clinical symptoms and signs of NEC/NEC like disease were divided into two groups as early (<= 7 days, ENEC) or late (> 7 days, CNEC) groups. Beside clinical variables, serum L-lactate, endothelin-1 (ET-1), platelet activating factor (PAF), and intestinal fatty acid binding protein (I-FABP) levels were measured from umbilical/peripheric venous blood in the first hour of life and during the clinical presentation in all groups. A total of 86 preterm infants were enrolled in the study. In the ENEC group, the incidences of fetal umbilical artery Doppler velocimetry abnormalities, IUGR, and delayed passage of first meconium were higher. In addition, mean levels of L-lactate, ET-1, PAF, and I-FABP were higher in the first hour of life. Conclusion: Our study firstly showed that the dominant pathophysiological factor of ENEC is prenatal hypoxic-ischemic event where intestinal injury and inflammation begin in-utero and become clinically apparent in the first week of life. Therefore, we propose a new term "Hypoxic-Ischemic Enterocolitis (HIEnt)" for the definition of ENEC in preterm infants with prenatal hemodynamic disturbances and IUGR. This new sight can provide individualized preventive and therapeutic strategies for preterm infants.What is Known:center dot The pathophysiology of early necrotizing enterocolitis (NEC) or NEC-like disease which is seen in the first week of life seems different than classic necrotizing enterocolitis (CNEC) which is always seen after the first week of life.What is New:center dot This study suggests that perinatal hypoxic-ischemic process with inflammation is the point of origin of fetal intestinal injury leading to ENEC.center dot We propose a new term "Hypoxic-Ischemic Enterocolitis (HIEnt)" for the definition and differentiation of this unique clinical entity.