OBJECTIVE There have been few studies of GH dose responses in Turner's syndrome. We have therefore compared the growth effect of two doses of subcutaneous rGH: 0.45 (D1) or 0.90 (D2) IU/kg/week.
DESIGN Multicentre study with two parallel randomized groups treated with D1 or D2 dose for one year, then with D2 for the second and third years in both groups.
PATIENTS Ninety-seven girls with Turner's syndrome aged from 4.8 to 16.5 years.
RESULTS The first mean height velocity (HV) was significantly higher with D2. At one year the girls changed from D1 to D2 showed a further acceleration in HV. During second and third years HV remained above the mean for untreated Turner girls, in both groups. Mean cumulative height gains over the 3 years were 1.06 and 1.17 SDS/CA (Ranke's Turner standard) in groups G1 and G2 respectively. Bone maturation, over 36 months, was 33.7 (G1) and 31.9 (G2) months.
CONCLUSION These results suggest that, if a higher initial GH dose is associated with a greater net initial height gain, the duration of treatment might affect the long-term results. Intermittent treatment should be considered.