So at the moment there are suggestions of all the following as risks for children who go onto puberty blockers followed by cross-hormones:
Reduction in IQ
Bone density not increasing as it should, leading to risk of osteoarthritis and osteoporosis
Delayed brain maturation and social development, lagging behind peers
Future risks of cardiovascular problems, stroke, cancer
Infertility
Inability to orgasm
Gender practitioners and transactivists say this is a price worth paying because if gender questioning children/teens don't get this treatment it's alleged they are at much increased risk of suicide/self-harm. Also: need bodies fixed to be closer match to brains.
But:
In the past 80% minimum desisted once they got through puberty.
High proportion of gender nonconforming children would grow up to be gay men/lesbians if they get the chance.
Plenty of evidence most children/teens with GD have any or all of family trauma, history of abuse, diagnosis of ASD, pre-existing MH problems, all ignored in favour of instant affirmation of child's statement that they are trans.
The suicide statistics appear to have been massively overstated.
Anecdotal evidence is building up all the time of detransitioners, left with permanent changes to their bodies and long-term health issues, all avoidable.
THERE IS NO EVIDENCE BASE FOR AFFIRMATION AS CURRENTLY BEING PRACTISED.