Abstract
Bone health in transmen and transwomen is an important issue that needs to be evaluated by clinicians. Prior to gender-affirming hormone treatment (GAHT), transwomen have lower bone mineral density (BMD) and a higher prevalence of osteopenia than cismen probably related to external factors, such as hypovitaminosis D and less physical activities. Gonadotropin-releasing hormone (GnRH) analogues in transgender youth may cause bone loss; however, the addition of GAHT restores or at least improves BMD in both transboys and transgirls. The maintenance or increase in BMD shown in short-term longitudinal studies emphasizes that GAHT does not have a negative effect on BMD in adult transwomen and transmen. Gonadectomy is not a risk factor if GAHT is taken correctly. The prevalence of fractures in the transgender population seems to be the same as in the general population but more studies are required on this aspect. To evaluate the risk of osteoporosis, it is mandatory to define the most appropriate reference group not only taking into consideration the medical aspects but also in respect of the selected gender identity of each person.