Effects of intrauterine growth retardation in premature infants on early childhood growth

Abstract

Objective: To evaluate in preterm infants the role of intrauterine growth retardation and infant body proportionality on subsequent childhood growth.

Methods: Preterm infants (818) prospectively enrolled in the Infant Health and Development Program were studied from birth to 36 months of corrected age. Weights and lengths were recorded at eight intervals. Growth parameters were compared in preterm infants with differing body symmetry at birth, defined by length-for-age and weight-for-age. Infants with both low length-for-age and low weight-for-age at birth were categorized as symmetrically growth retarded, and infants with normal length-for-age and low weight-for-age were categorized as asymmetrically growth retarded.

Results: Infants born with low length-for-age demonstrated increased growth velocity until 8 months of corrected age (p <0.001). However, infants born with low weight-for-age demonstrated decreased weight-gain velocity compared with preterm infants with appropriate weight for gestational age (AGA) until 40 weeks of corrected age (p <0.001). Heights and weights of infants with either symmetric or asymmetric intrauterine growth retardation remained significantly retarded compared with AGA preterm patients and the National Child Health Survey (NCHS) reference population (p <0.001). Infants born short but with normal weight did not significantly differ from AGA preterm infants in either weight or length at 36 months of corrected age. Preterm infants with both symmetric and asymmetric growth retardation demonstrated limited catch-up growth in weight until age 4 months and then paralleled the AGA preterm patients and the NCHS reference population. Very low birth weight (< or = 1250 gm), gestational age, and a broad-based day-care intervention did not influence growth outcome after control for the presence of intrauterine growth retardation.

Conclusions: Preterm infants with both symmetric and asymmetric intrauterine growth retardation demonstrate limited catch-up growth. Intrauterine growth deficits persist into early childhood.