Extrauterine growth restriction among neonates with a birthweight less than 1500 grams

Introduction: Growth restriction in preterm infants has been related to a poor neurodevelopment outcome. Objectives: To define the incidence of postnatal growth restriction in premature babies ≤1500 g and to detect related clinical or biochemical markers. Methods: Retrospective longitudinal observational study. Multivariate linear regression models were used to determine variables that can predict the change in weight z-score during admission. Results: The study included 130 patients with a mean birthweight of 1161 ± 251 g and a gestational age of 29.9 ± 2.5 weeks. At hospital discharge, 59.2% had a weight below P10. During admission, the z-scores of weight and length decreased by −0.85 ± 0.79 and −1.09 ± 0.65, respectively. The largest decrease in z-score occurred during NICU admission, with a weight gain rate of 6.6 ± 8.8 g/kg/day, after which growth acceleration took place (16.7 ± 3.8 g/kg/day), but was insufficient to catch-up. Higher levels of urea were negatively correlated with the change in the z-score of weight (P