Puberty represents a window of opportunity to build a strong skeleton. In TGD youth, the particular hormonal milieu and the altered timing of puberty can have a negative impact on bone growth and mineralization. To date, available literature data suggest to monitor BMD in order to protect bone health in all TGD adolescents undergoing puberty suppression for several years. In particular, trans girls present with BMD Z-scores below zero already at the start of gender transition and have a higher risk for impaired bone mass accrual. A calcium-rich diet, physical activity,, and weight-bearing exercise are encouraged for all TGD adolescents, and particular attention should be paid to those adolescents who have other risk factors for bone fragility or an unhealthy lifestyle.