[Effects of SERMs on bone health. Changes in bone metabolism in cases of gender identity disorder].

The aim of this study is that to investigate the influence of the sex hormones of different genders on adjustments for their bone metabolism. we retrospectively investigated changes in bone metabolism in patients with gender identity disorder and Klinefelter's Syndrome. In the patients who had been reassigned from male to female, we observed suppression of bone resorption and increment of BMD, and in the patients who had been reassigned from female to male, we observed acceleration of bone resorption and diminution of BMD. This indicates that estrogen is more important than testosterone for male and female bones and the efficacy of testosterone for female bones does not compensate for a shortage of estrogen. This result may suggest that SERM is also effective for male osteoporosis.