The aim was to evaluate postnatal growth of preterm infants in childhood and to determine factors that have an effect on catch-up growth (CUG). Ninety-six (42F, 54M) preterm born children with a gestational age of 32.6 +/- 2.9 weeks and birth weight of 1815 +/- 668 g were evaluated at age 4.7 +/- 1.1 years. Preterm children with birth weight and/or length below 10(th) percentile were accepted as small-for-gestational age (SGA) and those above as appropriate-for-gestational age (AGA). Height SDS was similar (-0.5 +/- 1.0) in preterm AGA and SGA children. Both groups had low body mass index (BMI) SDS (-0.6 +/- 1.4 and -1.0 +/- 1.5, respectively). Of the preterm SGA children, 65.8% showed a CUG in height and 3.8% catch- down growth. These rates were 24.6% and 33.5% in preterm AGA children. CUG in height was best explained by birth length and mother's height and CUG in weight by birth weight and mother's weight. In conclusion, although most of the preterm SGA children show CUG, they reach a compromised height in childhood. A number of preterm AGA children show a catch-down growth.