Summary

This review collected every study it could find, up to September 2023, on puberty blockers for young people with gender distress, and rated how trustworthy the evidence was. Only 10 studies qualified, and none was a randomised trial, where people are assigned to treatment by chance. The studies were small and often missing results for many people. Every result on mental health, gender distress and bone density was rated very low quality. Bone density seemed lower after treatment, and nearly all young people went on to cross-sex hormones. The authors conclude we cannot tell whether blockers help or harm, and call for better studies. Its findings match other independent reviews, including those for England's Cass Review. But it was funded by SEGM, a group critical of youth transition, it only searched English-language studies, and it misses newer studies.

Key findings

• 검토는 연구 10건을 찾았습니다. 3건은 차단제를 쓴 청소년과 쓰지 않은 청소년을 비교했고 7건은 같은 사람들을 전후로만 측정했습니다.
• 사람들을 우연으로 치료에 배정하는 무작위 시험은 없었습니다.
• 성별 불쾌감, 일상 기능, 우울에 대한 모든 근거는 매우 낮은 품질로 평가되어, 이익도 해도 배제할 수 없습니다.
• 비교 연구에서 일상 기능 점수는 12개월 후 차단제를 쓴 쪽이 다소 나아 보였지만, 결과가 너무 불확실해서 약간 나쁜 것부터 훨씬 좋은 것까지 무엇이든 의미할 수 있습니다.
• 고관절과 척추의 골밀도는 차단제 후 또래보다 뒤처졌지만, 이 근거도 매우 약하다고 평가되었습니다.
• 두 연구에서 차단제를 받은 청소년의 92%가 1~3년 안에 반대 성 호르몬으로 넘어갔습니다.
• 여러 연구는 청소년의 절반도 안 되는 수에 대한 결과만 있었고, 어떤 연구도 치료, 다른 정신 건강 상태, 가족 지원을 제대로 고려하지 않았습니다.
• 저자들은 청소년을 시간 순으로 추적하는 신중한 연구와, 윤리적으로 가능하다면 무작위 시험을 요구합니다.

Abstract

Aim Gender dysphoria (GD) refers to the psychological distress associated with the incongruence between one's sex and one's gender identity. To manage GD, individuals may delay the development of primary and secondary sex characteristics with the use of puberty blockers. In this systematic review, we assess and summarise the certainty of the evidence about the effects of puberty blockers in individuals experiencing GD. Methods We searched Medline, Embase, PsychINFO, Social Sciences Abstracts, LGBTQ+ Source and Sociological Abstracts from inception to September 2023. We included observational studies comparing puberty blockers with no puberty blockers in individuals aged <26 years experiencing GD, as well as before-after and case series studies. Outcomes of interest included psychological and physical outcomes. Pairs of reviewers independently screened articles, abstracted data and assessed risk of bias. We performed a meta-analysis and assessed the certainty of a non-zero effect using the grading of recommendations assessment, development and evaluation (GRADE) approach. Results We included 10 studies. Comparative observational studies (n=3), comparing puberty blockers versus no puberty blockers, provided very low certainty of evidence on the outcomes of global function and depression. Before-after studies (n=7) provided very low certainty of evidence addressing gender dysphoria, global function, depression, and bone mineral density. Conclusions There remains considerable uncertainty regarding the effects of puberty blockers in individuals experiencing GD. Methodologically rigorous prospective studies are needed to understand the effects of this intervention. Trial registration number PROSPERO CRD42023452171.

Conclusion

The best available evidence reporting the effects of puberty blockers in individuals with GD was mostly very low certainty and therefore we cannot exclude the possibility of benefit or harm. There was evidence available for the outcomes of global function, depression, GD, bone mineral density and progression to gender affirming hormone therapy. High certainty evidence from prospective cohort studies and, if ethical, RCTs, is needed to understand the short and long term effects of puberty blockers in individuals experiencing GD.