Symposium: neonatologyWhat growth should we aim for in preterm neonates?

Growth is a characteristic of all mammals and implies a progression from infancy to adulthood, as well as being an indication of nutritional adequacy. Growth is therefore important as a 'marker' of health and disease, rather than being a functional outcome in itself. Knowing the weight of a baby is essential in the neonatal intensive care unit (NICU) because it determines a whole range of practices, including estimation of daily fluid and nutrient intake needs, and determining drug doses. Weight thresholds may indicate changes in other management, such as when the baby can be moved from an incubator to an open cot, or perhaps when the baby is ready for discharge. Parents and families perceive weight gain as clear tangible proof that their baby is getting better. Parents are delighted when they see their baby has gained weight, and are generally concerned when they do not. The use of growth charts to plot growth with lines indicating apparent 'normal' growth trajectories may suggest to parents (and perhaps staff) that we know what is best. However, the optimal speed of weight gain, or growth, remains a matter of uncertainty: rapid growth may be harmful, slow growth might sometimes be acceptable. Growth must be seen in the context of optimising nutritional status, rather than simply achieving increases in auxological parameters. In this review we describe the science underpinning current thinking in nutritional management of babies on the neonatal care unit, give guidance for optimal nutrition and outline the short, medium and long term consequences of early nutritional care.