Effect of Spironolactone and Cyproterone Acetate on Breast Growth in Transgender People: A Randomized Clinical Trial
Authors' conclusion
Antiandrogen choice should be based on clinician and patient preference with consideration of side effects. Further research is needed to optimize breast development in transgender people.
Study context
- Population
- Transgender people aged 18+ years, sex recorded male at birth, commencing feminizing gender affirming hormone therapy; 2020–2022; median age 25 yearsITT analysis
- Participants
- 63 people
- Comparison
- Cyproterone acetate vs spironolactone, each with standardized estradiol
- Cyproterone acetaten = 32
- Spironolactonen = 31reference
- Primary endpoint
- Breast development measured by breast-chest distance
- Follow-up
- 6 months
Methodological detailssingle-centre outpatient endocrinology clinic
- Single-centre outpatient endocrinology clinic
Primary result
Breast-chest distance
Mean difference
0.27 cm
95% CI −0.82 to 1.35
P = 0.6
Between Cyproterone acetate and Spironolactone
mean difference 0.27 cm (95% CI −0.82 to 1.35); P = 0.6
As reported in the abstract
Secondary outcomes
| Outcome | Mean difference (mL) (95% CI) | P value | |
|---|---|---|---|
| Estimated breast volume · 6 monthsNo between-group difference | 17.26 (−16.94 to 51.47) | P = 0.3 | |
| −50050100Difference, mL (linear scale) |
| Outcome | OR (95% CI) | P value |
|---|---|---|
| Suppression of serum testosterone to <2 nmol/L | 9.01 (1.83–4.44) | P = 0.008 |
- Suppression of serum testosterone to <2 nmol/L: more likely with cyproterone acetate; estimate outside printed CI
Change in Gender Preoccupation and Stability Questionnaire (GPSQ)
- Changes in GPSQ were similar between groups
Original publication
Effect of Spironolactone and Cyproterone Acetate on Breast Growth in Transgender People: A Randomized Clinical Trial. J Clin Endocrinol Metab. Published 17 September 2024. doi:10.
Composed by AI from the published abstract and checked against it. How Briefs are made →