We retrospectively analyzed the effects of recombinant human growth hormone (rhGH) in a Belgian population of 36 short children with renal allografts. Seven children were dropped from the growth study: 1 had skeletal dysplasia and in 6 cases rhGH was given for less than 1 yr (1 died, 1 developed genu valgum, 2 were non-compliant and 2 grafts deteriorated). Final height was reached in 17 patients, and 12 children were still growing at the end of the study. Median height standard deviation score (SDS) in the 29 patients was -2.3 at the time of transplantation, and -2.7 when rhGH therapy was initiated. During rhGH therapy (median duration 3.2 yr, range 0.6-7.7 yr), height SDS increased by a mean of 0.4 per year, and bone maturation was not accelerated. Final height reached was 162.7 (149.0-169.5) cm (median SDS -1.8) in males and 151.0 (130.5-169.5) cm (median SDS -1.9) in females. Final height is significantly greater in males than females compared with a historical control group of untreated patients. Final height is within the parental target height range in 6 out of the 17 patients. The increase in height SDS in patients who were at an advanced stage of puberty (Tanner stages 4-5) when rhGH therapy was initiated exceeded our expectations (mean height gain 14.2 cm in boys and 10 cm in girls). In the cohort of 36 children, 4 patients developed an acute allograft rejection, all of whom had an underlying chronic rejection. This resulted in 3 graft losses within 5 yr. Our results indicate that rhGH treatment has a positive effect in short children with renal allografts, even if it is started in late puberty. In the presence of underlying chronic rejection, rhGH treatment needs careful monitoring to minimize the risk of graft loss.