We measured the final height (FH) of 25 short polytransfused thalassemia major (Th) patients (18 males) with a reduced GH reserve treated for 3.3 +/- 1.2 yr with recombinant GH (rhGH), 0.2 mg/kg/week sc. At baseline, all patients were clinically prepubertal; their chronological (CA) and bone ages (BA) were 13.6 +/- 2.0 and 11.4 +/- 1.6 yr, respectively. In 9 out of 18 males and 5 out of 7 females, the onset of puberty occurred spontaneously during the treatment. At the end of the rhGH administration, the height of the enrolled children was not significantly increased when calculated for CA (HxCA), while it was significantly decreased (p=0.004) when calculated for BA (HxBA); the BA increase (3.29 +/- 1.65 yr) was significantly higher (p<0.001) than the height age increase (2.16 +/- 0.98 yr). The FHxCA showed a significant increase (p=0.001) compared to both baseline and the end of therapy, while the FHxBA was significantly decreased (p<0.001) compared with the corresponding value at baseline. At the end of therapy, both HxCA and HxBA resulted positively related to the BA at baseline (r=0.50 and 0.42, p=0.012 and 0.034, respectively). FH was positively correlated with CA (r=0.63, p=0.001), BA (r=0.68, p<0.001) and HxBA (r=0.59, p=0.002) evaluated at baseline, and with both HxCA and HxBA (r=0.82 and 0.74, respectively, p<0.001), evaluated at the end of treatment. A negative correlation was found between FH and the length of treatment (r=-0.56, p=0.004). Our data seem to exclude that prolonged rhGH therapy could improve FH in Th patients; on the contrary, a negative effect may be hypothesized.