Optimising growth in very preterm infants: reviewing the evidence.

Infants born before 32 weeks' postmenstrual age are at a high risk of growth failure. International guidelines have long recommended that they match the growth of an equivalent fetus, despite the challenges posed by ex utero life and comorbidities of prematurity. Several groups have recently questioned the necessity or desirability of this target, shifting attention to aiming for growth which optimises important long-term outcomes. Specifically, recent research has identified the neurodevelopmental benefits of enhanced growth during the neonatal period, but work in term infant suggests that rapid growth may promote the metabolic syndrome in later life. In this context, defining a pattern of growth which optimises outcomes is complex, controversial and contested. Even if an optimal pattern of growth can be defined, determining the nutritional requirements to achieve such growth is not straightforward, and investigations into the nutritional needs of the very preterm infant continue. Furthermore, each infant has individual nutritional needs and may encounter a number of barriers to achieving good nutrition. This article offers a narrative review of recent evidence for the competing definitions of optimal growth in this cohort. It examines recent advances in the determination of macronutrient and micronutrient intake targets along with common barriers to achieving good nutrition and growth. Finally, key implications for clinical practice are set out and a recommendation for structured multidisciplinary management of nutrition and growth is illustrated.