TOPLINE:

Overweight, obesity, and dyslipidaemia were common in transgender adolescents before hormone therapy. Sex steroid therapy affected lipid profiles differently in transgender boys and girls, with trans boys showing decreases in high-density lipoprotein (HDL) levels and increases in triglyceride levels and trans girls experiencing increases in HDL levels during treatment.

METHODOLOGY:

• Researchers in Denmark conducted an observational study of 219 transgender adolescents (164 trans boys; mean age, 16 years; 53 trans girls; mean age, 15.7 years) who initiated hormone therapy before the age of 18 years to examine changes in weight, BMI, and lipid profiles before and during treatment.
• Pubertal suppression was achieved with gonadotropin-releasing hormone analogues (GnRHa), initiated either before or alongside sex steroid therapy.
• Trans boys received testosterone therapy via transdermal gel; trans girls received oestradiol via patches/gel and, in some cases, tablets.
• Participants were assessed at baseline, which was within 12 months before treatment initiation, and during routine visits every 3-6 months.

TAKEAWAY:

• At baseline, trans boys had higher rates of overweight and obesity and more frequently had elevated low-density lipoprotein levels (≥ 3 mmol/L), whereas trans girls more often had low HDL levels (≤ 1 mmol/L).
• During GnRHa monotherapy, neither group had meaningful changes in BMI; lipid profiles remained unchanged, except for an increase in total cholesterol levels after 1 year in trans girls.
• After starting testosterone therapy, trans boys showed an initial increase in BMI, followed by a decline after 2 years (P < .05 for both); the initiation of oestradiol in trans girls tended to show an increase in BMI after 1 year.
• Across 3 years of sex steroid treatment, HDL levels decreased significantly in trans boys and increased in trans girls; triglyceride levels rose over 3 years only in trans boys.

IN PRACTICE:

"This study emphasizes the importance of lifestyle interventions, such as encouraging physical activity and prevention of tobacco use, as part of the treatment program for transgender youths, even before any HT [hormone therapy] is initiated," the authors of the study wrote.

SOURCE:

This study was led by Kjersti Kvernebo Sunnergren, Göteborg Pediatric Growth Research Center, Institute of Sciences, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden, and Pernille Badsberg Norup, Copenhagen University Hospital — Rigshospitalet, Copenhagen, Denmark. It was published online on October 07, 2025, in The Journal of Clinical Endocrinology & Metabolism.

LIMITATIONS:

The study's short follow-up prevented repeated measurements. The cohort was predominantly White, which may have limited generalisability to other ethnic groups. As the study was conducted in a clinical setting, it was prone to missing data, and relying only on weight and BMI may not have fully reflected the effects of hormone therapy on lean body mass.

DISCLOSURES:

This study was financially supported by the Novo Nordisk Foundation; Sundhedsstyrelsen; Futurum - Akademin för Hälsa och Vård, Region Jönköpings län; and Sygeforsikringen "danmark." One author reported serving on the speakers bureau for Gedeon Richter.

This article was created using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication.