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Updated: Sep 3, 2025

Establishment of Rat Models Mimicking Gender-affirming Hormone Therapies
Published on: January 10, 2025
Trajectories of transgender adolescents referred for endocrine intervention in England
Una Masic1, Gary Butler2, Paul Carruthers3
1Gender Identity Development Service, Tavistock and Portman NHS Foundation Trust, London, UK umasic@tavi-port.nhs.uk.
Objectives:
Some gender-diverse young people (YP) who experience clinically significant gender-related distress choose to pursue endocrine treatment alongside psychotherapeutic support to suppress pubertal development using gonadotropin-releasing hormone analogues (GnRHa), and then to acquire the secondary sex characteristics of their identified gender using gender affirming hormones (GAH). However, little is known about the demographics of transgender adolescents accessing paediatric endocrinology services while under the specialist Gender Identity Development Service (GIDS) in England.
Design:
Demographics of referrals from the GIDS to affiliated endocrinology clinics to start GnRHa or GAH between 2017 and 2019 (cohort 1), with further analysis of a subgroup of this cohort referred in 2017-2018 (cohort 2) were assessed.
Results:
668 adolescents (227 assigned male at birth (AMAB) and 441 assigned female at birth (AFAB)) were referred to endocrinology from 2017 to 2019. The mean age of first GIDS appointment for cohort 1 was 14.2 (±2.1) years and mean age of referral to endocrinology postassessment was 15.4 (±1.6) years. Further detailed analysis of the trajectories was conducted in 439 YP in cohort 2 (154 AMAB; 285 AFAB). The most common pathway included a referral to access GnRHa (98.1%), followed by GAH when eligible (42%), and onward referral to adult services when appropriate (64%). The majority (54%) of all adolescents in cohort 2 had a pending or completed referral to adult services.
Conclusions:
This study highlights the trajectories adolescents may take when seeking endocrine treatments in child and adolescent clinical services and may be useful for guiding decisions for gender-diverse YP and planning service provision.
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