Interventions to suppress puberty in adolescents experiencing gender dysphoria or incongruence: a systematic review

Background Treatment to suppress or lessen effects of puberty are outlined in clinical guidelines for adolescents experiencing gender dysphoria/incongruence. Robust evidence concerning risks and benefits is lacking and there is a need to aggregate evidence as new studies are published.Aim To identify and synthesise studies assessing the outcomes of puberty suppression in adolescents experiencing gender dysphoria/incongruence.Methods A systematic review and narrative synthesis. Database searches (Medline, Embase, CINAHL, PsycINFO, Web of Science) were performed in April 2022, with results assessed independently by two reviewers. An adapted version of the Newcastle-Ottawa Scale for cohort studies was used to appraise study quality. Only moderate-quality and high-quality studies were synthesised. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses reporting guidelines were used.Results 11 cohort, 8 cross-sectional and 31 pre-post studies were included (n=50). One cross-sectional study was high quality, 25 studies were moderate quality (including 5 cohort studies) and 24 were low quality. Synthesis of moderate-quality and high-quality studies showed consistent evidence demonstrating efficacy for suppressing puberty. Height increased in multiple studies, although not in line with expected growth. Multiple studies reported reductions in bone density during treatment. Limited and/or inconsistent evidence was found in relation to gender dysphoria, psychological and psychosocial health, body satisfaction, cardiometabolic risk, cognitive development and fertility.Conclusions There is a lack of high-quality research assessing puberty suppression in adolescents experiencing gender dysphoria/incongruence. No conclusions can be drawn about the impact on gender dysphoria, mental and psychosocial health or cognitive development. Bone health and height may be compromised during treatment. More recent studies published since April 2022 until January 2024 also support the conclusions of this review.PROSPERO registration number CRD42021289659.