An important review of the research into transgender care has just been published by by two American accademics. See the abstract below (the article itself is open access).

In terms of context, there is a marked contrast emerging between a ‘trans-European’ (trans meaning across, not transgender) approach, now including leading medical research institutes in Finland, Sweden, Norway France, and England, which are all urging extreme caution in providing gender affirming psychological, pharmacological and surgical interventions for children and adolescents identifying as trans; and the US consumer healthcare model where such interventions are strongly promoted at federal and state level (except for Florida). The change in medical policy within Europe is based on systematic reviews (in the absence of randomised controlled trials) which show few (if any) benefits to young patients and a dearth of long-term outcome studies to validate the expectation that benefits are maintained across the lifespan. US transgender healthcare (I.e. WPATH Standards of Care 8) continue to insist that gender affirming medical care is essential, despite the fact that there is no robust evidence base to support this. In the absence of evidence, WPATH’s sole justification is that this is what patients are asking for, representing in medico-ethical terms, the triumph of client autonomy over non-maleficence.

Stephen B. Levine and E. Abbruzzese, “Current Concerns About Gender‑Affirming Therapy in Adolescents”, Current Sexual Health Reports, Published online April 14th 2023, https://doi.org/10.1007/s11930-023-00358-

ABSTRACT (final sentence has been bolded)

Purpose of Review Results of long-term studies of adult transgender populations failed to demonstrate convincing improvements in mental health, and some studies suggest that there are treatment-associated harms. The purpose of this review is to clarify concerns about the rapid proliferation of hormonal and surgical care for the record numbers of youth declaring transgender identities and seeking gender reassignment procedures.
Recent Findings Systematic reviews of evidence conducted by public health authorities in Finland, Sweden, and England concluded that the risk/benefit ratio of youth gender transition ranges from unknown to unfavorable. As a result, there has been a shift from “gender-affirmative care,” which prioritizes access to medical interventions, to a more conservative approach that addresses psychiatric comorbidities and psychotherapeutically explores the developmental etiology of the trans identity.
Debate about the safety and efficacy of “gender-affirming care” in the USA is only recently emerging.
Summary The question, “Do the benefits of youth gender transitions outweigh the risks of harm?” remains unanswered because of a paucity of follow-up data. The conclusions of the systematic reviews of evidence for adolescents are consistent with long-term adult studies, which failed to show credible improvements in mental health and suggested a pattern of treatment-associated harms. Three recent papers examined the studies that underpin the practice of youth gender transition and found the research to be deeply flawed. Evidence does not support the notion that “affirmative care” of today’s adolescents is net beneficial. Questions about how to best care for the rapidly growing numbers of gender-dysphoric youth generated an intensity of divisiveness within and outside of medicine rarely seen with other clinical uncertainties. Because the future
well-being of young patients and their families is at stake, the field must stop relying on social justice arguments and return to the time-honored principles of evidence-based medicine