Cohort study showed that growth rate increment has not been enough to prevent growth retardation of preterm infants and raised concerns about unbalanced growth

Abstract

We describe the postnatal weight gain, linear and head growth trends of surviving preterm infants from 2005 to 2017. Multicentre cohort study, including surviving preterm infants <32weeks (n=21084), from the Spanish Neonatal Network database, without major congenital malformations who were less than 50weeks postmenstrual age at discharge. Outcomes were weight gain (g/kg/day), linear and head growth (cm/week) and changes in weight, length and head circumference z-scores from birth to discharge. The study period was divided into 2005-8, 2009-11, 2012-14 and 2015-17. Weight gain, linear growth and head growth were slightly higher in 2015-2017 than in 2005-2008: 12.2±2.6 to 13.1±2.5g/kg/day, 0.98±0.6 to 1.03±0.6cm/week and 0.76±0.2 to 0.77±0.3cm/week, respectively. It was associated with a decreased fall in weigh, length and head circumference z-scores from birth to discharge (-1.32±0.9 to -1.01±0.84, -1.38±1.2 to -1.18±1.2 and -0.41±1.2 to -0.33±1.3, respectively). Postnatal growth restriction remained a common complication of prematurity despite some increment over the last years. Growth disproportionality seemed to be worsening as weight gain was increased more than linear growth.