RESUMO
BACKGROUND: Constitutional advancement of growth (CAG) is the growth pattern of early growth acceleration that has been shown to be characteristic in girls with idiopathic precocious puberty (IPP). The aim of this study was to examine the growth pattern of girls with early puberty compared to girls with IPP. METHODS: We studied the growth pattern, from birth to presentation, of 61 girls with early puberty, of 40 girls with IPP and of 100 healthy girls with normal pubertal onset that served as controls. RESULTS: Height SDS (HSDS) at presentation was significantly different among the 3 groups (p < 0.001). Girls with early puberty were shorter than girls with IPP (HSDS 0.63 ± 1.09 vs. 0.98 ± 0.95, respectively, p < 0.001) and taller than control girls (HSDS 0.05 ± 0.94, p < 0.05). By comparing the linear growth pattern from birth to presentation, pairwise comparisons showed that it differed significantly between early puberty and control (p < 0.001) as well as between IPP and control girls (p < 0.001), whereas the difference between girls with IPP and early puberty was not significant (p = 0.09). CONCLUSION: Girls with early puberty present the pattern of CAG suggesting that IPP lies at the extreme of the distribution of the normal timing of puberty onset.