Final height in girls with Turner's syndrome treated with once or twice daily growth hormone injections

Objectives-To study final height in girls with Turner's syndrome treated wi th once or twice daily injections of growth hormone (GH) in combination wit h low dose ethinyl oestradiol. Design-Until final height was reached, the effect of fractionated subcutane ous injections given twice daily was compared with once daily injections of a total GH dose of 6 IU/m(2)/day. Twice daily injections were given as one third in the morning and two thirds at bedtime. All girls concurrently rec eived low dose oestradiol (0.05 mu g ethinyl oestradiol/kg/day, increased t o 0.10 mu g/kg/day after 2.25 years). Patients-Nineteen girls with Turner's syndrome aged greater than or equal t o 11 years (mean (SD) 13.6 (1.7) years). Measurements-To determine final height gain, we assessed the difference bet ween the attained final height and the final height predictions at the star t of treatment. These final height predictions were calculated using the Ba yley-Pinneau (BP) prediction method, the modified projected adult height (m PAH), the modified index of potential height (mIPH(RUS)), and the Turner's specific prediction method (PTSRUS). Results-The gain in final height (mean (SD)) was not significantly differen t between the once daily and the twice daily regimens (7.6 (2.3) v 5.1 (3.2 ) cm). All girls exceeded their adult height prediction (range, 1.6-12.3 cm ). Thirteen of the 19 girls had a final height gain > 5.0 cm. Mean (SD) att ained final height was 155.5 (5.4) cm. A "younger bone age" at baseline and a higher increase in height standard deviation score for chronological age (Dutch-Swedish-Danish references) in the first year of GH treatment predic ted a higher final height gain after GH treatment. Conclusions-Division of the total daily GH dose (6 IU/m(2)/day) into two th irds in the evening and one third in the morning is not advantageous over t he once daily GH regimen with respect to final height gain. Treatment with a GH dose of 6 IU/m(2)/day in combination with low dose oestrogens can resu lt in a significant increase in adult height in girls with Turner's syndrom e, even if they start GH treatment at a relatively late age.