Pubertal course of persistently short children born small for gestational age (SGA) compared with idiopathic short children born appropriate for gestational age (AGA)

Objective: Few data are available on the pubertal development of children born small for gestational age (SGA) who fail to show catch-up growth. Design: A longitudinal analysis compared the pubertal course of persistently short children born SGA compared to children with idiopathic short stature who were appropriate for gestational age (AGA). One hundred and twenty-eight short children (height SDS < - 1.7), including 76 (31 boys) born SGA and 52 (22 boys) born AGA, were regularly followed from early childhood to completion of puberty. Results: Puberty was attained at normal age (10.5-14 years in boys, 9.5-13 years in girls) for most children in both the SGA and AGA groups (boys, 80% and 77%; girls, 76% and 78% respectively). The duration of puberty was similar in the SGA and AGA groups. Menarche occurred at normal age range but was significantly earlier in the SGA girls (P < 0.01 by ANOVA). Despite the similar total pubertal growth, the patterns of growth differed significantly: SGA group - accelerated growth and bone maturation rates from onset of puberty with peak height velocity at Tanner stages 2 - 3, followed by a decelerated growth rate and earlier fusion of the epiphyses; AGA group - steady progression of bone elongation and maturation throughout puberty (pubertal growth, P < 0.05 in both sexes; bone maturation, P < 0.001 in both sexes). Final height in the SGA group was compromised compared with their target height (P < 0.001). Conclusion: Children born SGA have a normal pubertal course with a distinct pubertal growth pattern. This pattern may represent an altered regulation of their growth modalities.