Bone Maturation as a Predictive Factor of Catch-Up Growth During the First Year of Life in Born Small for Gestational Age Infants: A Prospective Study

Abstract

Background: About 85–90% of children born small for gestational age (SGA) experience a catch-up growth that occurs mostly during the first year of life and results in a full stature recovery by the age of 2. Objective: To investigate the relation between bone maturation (BM) and catch-up growth during the first year of life in SGA infants. Method: Newborns whose weight and/or length was <3 mm at birth, meaning intrauterine delay of BM). Results: Significantly higher height velocity (HV) was observed in subgroup A2 vs. A1 (32.4 ± 8.0 vs. 25.6 ± 2.9 cm, p = 0.01); nevertheless, more subjects in subgroup A2 had height < 0.001) but positively correlates with NB growth (r = 0.52, p < 0.01). Moreover, SGA babies with intrauterine delay of BM showed higher HV and better height gain at 12 months' evaluation than did SGA with adequate BM (29.75 ± 3.1 vs. 23.8 ± 2.7 cm, p = 0.003). Conclusion: Neonatal BM should be regarded as a predictive factor of SGA height gain during the first year of life. US evaluation of NB is a useful noninvasive technique to identify intrauterine delay of BM, which positively correlates with early postnatal catch-up growth of SGA infants.