Some medical professionals disagree that adolescents are cognitively mature enough to make a decision with regard to hormone therapy or surgery, and advise that irreversible genital procedures should not be performed on individuals under the age of legal consent in their respective country.A review published in Child and Adolescent Mental Health found that puberty blockers are fully reversible, and that they are associated with such positive outcomes as decreased suicidality in adulthood, improved affect and psychological functioning, and improved social life.In 2020, a review article commissioned by NHS England was published by the National Institute for Health and Care Excellence, concluding that the quality of evidence for puberty blocker outcomes (for mental health, quality of life and impact on gender dysphoria) was of very low certainty based on the GRADE scale. In the UK, Bell v Tavistock considered the case of a patient who had changed her mind, now believing she was too young to have made such a decision, and concluded "Where the decision is significant and life changing then there is a greater onus to ensure that the child understands and is able to weigh the information". Following the ruling, NHS England announced that children under 16 would no longer be given puberty blockers without court authorization.
By contrast, the majority of major medical associations define attempts to change an individuals gender identity or gender expression as conversion therapy.Treatment may also take the form of puberty blockers (such as leuprorelin), cross-sex hormones (i.e., administering estrogen to a child assigned male at birth or testosterone to a child assigned female at birth), or sex reassignment surgery with the aim of bringing ones physical body in line with their identified gender. Delaying puberty allows for the child to mentally mature while preventing them from developing a body they may not want, so that they may hopefully make a more informed decision about their gender identity once they are an adolescent. It can also help reduce anxiety and depression.According to the American Psychiatric Association, "Due to the dynamic nature of puberty development, lack of gender-affirming interventions (i.e. social, psychological,
and medical) is not a neutral decision; youth often experience worsening dysphoria and negative impact on mental health as the incongruent and unwanted puberty progresses. Trans-affirming treatment, such as the use of puberty suppression, is associated with the relief of emotional distress, and notable gains in psychosocial and emotional development, in trans and gender diverse youth".In its position statement published December 2020, the Endocrine Society stated that there is durable evidence for a biological underpinning to gender identity and that pubertal suppression, hormone therapy, and medically indicated surgery are effective and relatively safe when monitored appropriately and have been established as the standard of care.