To examine the growth and body composition of small for gestational age (SGA) and appropriate for gestational age (AGA) very low birth weight infants (VLBW) and their outpatient neurodevelopmental outcomes. From 2006–2012, VLBW infants (n = 57 of 92) admitted to the Neonatal Intensive Care Unit (NICU) had serial air displacement plethysmography (ADP) scans and were followed as outpatients. Serial developmental testing (CAT/CLAMS, Peabody Gross Motor Scales) and anthropometrics were obtained from n = 37 infants (29 AGA and 8 SGA) and analyzed via repeated measures analyses of variances. The percentage of body fat, percentage of lean mass, and weight gain were statistically significant between SGA and AGA groups at the first ADP assessment. There was no difference between the two groups in outpatient neurodevelopmental testing. Weight gain as “catch-up” body fat accrual occurs by 67 weeks of PMA. This catch-up growth is associated with normal SGA preterm neurodevelopment as compared to AGA preterm infants.

Introduction: Body composition, specifically fat-free mass (FFM), of preterm infants is associated with improved neurodevelopmental outcomes. Little is known about body composition of preterm infants after discharge. Preterm body composition was measured by air displacement plethysmography (ADP) at two time points, inpatient (35–40 weeks postmenstrual age [PMA]) and outpatient (48–58 weeks PMA), with neonatal factors and neurodevelopmental testing at 4–6 months corrected age. We hypothesized increased FFM is positively associated with neurodevelopment. Methods: From 2007 to 2011, 510 infants admitted to the Medical University of South Carolina’s neonatal intensive care unit underwent ADP. A total of 379 of 510 (74%) had anthropometrics at birth, an ADP scan with FFM, fat mass, fat percent z-scores, and an outpatient neurodevelopmental evaluation (CAT/CLAMS, Peabody Gross Motor). Variables were compared using multivariate analyses for body composition measurements. Results: The infants were 32 ± 4.8 weeks gestational age at birth with an average birth weight of 1,697 ± 932 g. Most (56%) infants received maternal milk at discharge. CAT, CLAMS, and gross motor scores had positive correlations with FFM z-scores at inpatient and outpatient ADP (p < 0.05). Receiving maternal milk at discharge was positively associated with cognitive (β = 0.22, p < 0.05) and language scores (β = 0.26, p < 0.05). Conclusion: Increased FFM is associated with improved cognitive, language, and gross motor testing. Maternal milk was positively associated with language and cognitive scores.