Monitoring the growth of preterm infants during and after their stay in the neonatal intensive care units: A focus on WHO growth curves after discharge

The growth curves routinely used for monitoring preterm infants are four decades old and may not be suitable for the current population. Intrauterine growth rate theoretically appears to be the ideal growth that needs to be replicated in the immediate postnatal period, but this may not be feasible given the limitations set by the morbidities of prematurity. Postnatal growth curves describe the actual growth of the preterm infants during their stay in neonatal units and are descriptive rather than prescriptive. The Fenton chart which has updated the Babson and Benda's chart with data from very large sample size of preterm infants born in the last two decades appears to be suitable for monitoring growth of preterm infants during their stay in the neonatal units. After discharge from the neonatal intensive care units and post-conceptional age of 40 weeks is reached, the recently released WHO growth curves appear suitable for monitoring their ongoing growth. While aiming to achieve intrauterine growth velocities in the immediate postnatal life, one should not overlook the potential short-term (e.g. necrotising enterocolitis and broncho-pulmonary dysplasia) and long-term (excessive catch-up growth with cardiovascular morbidity and diabetes) adverse effects of aggressive nutrition. Further research is needed to identify the best growth curves for monitoring these high-risk infants.