LAUSR

Abstract Introduction Postnatal growth restriction is considered a universal problem in extremely premature infants (EPI), and causes great concern due to the possible relationship between nutrition, sub-optimal postnatal growth, and neurodevelopment delay. Objectives To describe the weight gain in EPI and to determine the changes in the length and head circumference (HC) at hospital discharge in survivors. Patients and methods The study included 4520 Caucasian EPI from single pregnancies and without severe malformations, born in the centres participating in the Spanish SEN1500 network (2002–2011). The weight was recorded at birth, 28 days, 36 weeks post-menstrual age (PMA), and at discharge. The length and HC were measured at birth and at discharge. Results The rate of weight gain (exponential method) was 8.0 g/kg/day (birth to 28 days); 14.3 g/kg/day (28 days to 36 weeks); and 11.7 g/kg/day (36 weeks to discharge). At discharge, postnatal growth restriction was greater for length (z-score between −1.78 and −2.42, depending on GA), followed by weight (−1.67 to −1.79), and HC (−0.69 to −0.81). Conclusions Weight gain in the first weeks after birth is slow in EPI, and they exhibit an almost universal postnatal growth restriction that involves mainly length and weight. In addition to weight, a close control of longitudinal growth and HC are essential for nutritional assessment and detection of patients at risk for poor growth and neurodevelopment after hospital discharge.