Evaluation of postnatal growth of preterm infants.

The past two decades have seen a progressive improvement in the survival rates of preterm infants, especially in neonates <30 weeks of gestational age. These neonates constitute the large majority of the population in neonatal intensive care units. The correct evaluation of postnatal growth of these babies is nowadays of primary concern, although the definition of their optimal postnatal growth pattern is still controversial. Concerns have also been raised about the strategies to monitor their growth, specifically in relation to the charts used. At present the available charts in clinical practice are fetal growth charts, neonatal anthropometric charts and postnatal growth charts for term infants. None of these, for different reasons, is suitable to correctly evaluate preterm infant growth. An international multicentric project has recently started a study aiming at building a prescriptive standard for the evaluation of postnatal growth of preterm infants and it will be available in the next years providing a population that is conceptually as close as possible to the prescriptive approach used for the construction of the WHO infant and child growth standards. At present, while an international longitudinal standard for evaluating preterm infant postnatal growth is lacking, in Italy the best compromise in clinical practice is likely to be as follows: new Italian INeS (Italian Neonatal Study) charts up to term; International longitudinal charts WHO 2006 or CDC 2002 from term to two years; finally the Italian Society for Pediatric Endocrinology and Diabetes (SIEDP) 2006 growth charts could be suitable for monitoring the growth of these infants from two years up to 20 years of age.