PURPOSE:Decreased bone mineral density(BMD) has been reported in girls with Turner syndrome. Estrogen therapy is recommanded to improve sexual infantilism and decreased BMD. Short stature is also characteristic finding in patients with Turner syndrome. Treatment modality for short stature has included estrogen, anabolic steroids and growth hormone(GH). Recently GH therapy in GH deficient children could increase BMD in addition to improve short stature. We observed the treatment effects on bone mineral density in patients with Turner syndrome. METHODS: Bone Mineral Density in second to fourth lumbar spine area were measured by dual energy X-ray absorptiometry in 56 girls with Turner syndrome, before and after growth hormone and/or estrogen. All Turner girl was confirmed by clinical and chromosomal examination. RESULTS: 1) There was no significant difference in BMD according to karyotype. 2) The mean BMD of untreated Turner syndrome was 0.752+/-0.122g/cm2. 3) The mean BMD before and after GH treatment were 0.620+/-0.028g/cm2, 0.793+/-0.093g/cm2 respectively. The mean BMD before and after estrogen treatment were 0.761+/-0.125g/cm2, 0.918+/-0.141g/cm2 respectively. In combined group, the BMD were 0.752+/-0.087g/cm2 and 0.939+/-0.134g/cm2. Growth hormone was also effective to improve BMD as well as estrogen. But the changes of BMD were more significant in estrogen and combined group(p<0.05). 4) A significant positive correlation was found between age and BMD(p<0.05). CONCLUSIONS:Estrogen therapy can accelerate epiphysial maturation and compromise final height. Growth hormone therapy in Turner girls was effective for improvement bone mineral density as well as growth improvement. But growth hormone and estrogen combined therapy or Estrogen therapy is more effective to improve bone mineral density in Turner syndrome. Estrogen replacement can be delayed for a while on growth hormone treatment and the appropriated time of estrogen therapy should be elucidated.