Growth in small-for-gestational-age preterm-born children from 0 to 4 years: the role of both prematurity and SGA status.

BACKGROUND Fullterm small-for-gestational-age children (SGAs) are known for their ability to catch up on growth. Nevertheless, increased risk of growth restriction remains. Evidence on preterm SGA children's growth is lacking. OBJECTIVE To determine absolute gains in height and weight, relative growth, and growth restriction in preterm SGAs from 0 to 4 years and how prematurity and SGA status affect these measures. DESIGN/METHODS Community-based cohort study, n = 1,648 preterm-born (gestational age <36 weeks, 57 SGA) and 605 term-born (12 SGA). We defined SGA as a birth weight less than -2 SD (P 2.3) compared to counterparts matched for gestational age. Height, weight, and head circumference were obtained from medical records and translated to z-scores. We defined growth restriction as height or weight less than -2 SD compared to fullterm appropriate-for-gestational-age children (AGAs). RESULTS Absolute height and weight gains were similar, but the relative growth of preterms and fullterms differed. Preterm AGAs and fullterm SGAs, although not reaching it, caught up towards the fullterm AGA median (z-scores at 4 years: -0.3 to -1.0). By contrast, preterm SGA children's z-scores were still -1.4 to -1.7. Head circumference growth was less affected by prematurity and SGA birth (z-scores at 1 year: 0.1 to -0.7). Catch-up growth mainly took place during infancy. 30-39% of all preterm SGAs showed growth restriction at 4 years. CONCLUSIONS Growth in preterm SGAs is affected considerably by the joint effects of preterm birth and SGA status, resulting in a high proportion of growth restriction.