Presenter Status
Fellow
Abstract Type
Clinical Research
Primary Mentor or Principal Investigator
Michelle Knoll
Presentation Type
Poster
Start Date
19-5-2026 11:00 AM
End Date
19-5-2026 12:00 PM
Abstract Text
Objectives: Erythrocytosis is a recognized complication of testosterone therapy, yet adolescent-specific safety data remain limited. We sought to determine the incidence of erythrocytosis and characterize hematocrit trajectories in transgender adolescents receiving injectable testosterone esters.
Methods: We conducted a retrospective chart review of transgender adolescents and young adults initiating gender-affirming testosterone therapy at a pediatric endocrinology referral center (2012-2021). Patients receiving injectable testosterone esters (cypionate or enanthate) for ≥3 months with serial hematocrit monitoring were included. The primary outcome was erythrocytosis, defined as hematocrit ≥50%. Pearson correlations assessed relationships between treatment duration, cumulative dose, and maximum hematocrit.
Results: Eighty-nine patients were included (median age 16.4 years, IQR 15.7-17.4). Median baseline hematocrit was 39.7% (IQR 38.5-42.3); no patients had elevated hematocrit at baseline. Mean treatment duration was 38.8 months (range 10-142). Erythrocytosis occurred in 11/89 patients (12.4%). Mean maximum hematocrit was 46.3% (SD 3.1). Both treatment duration (r=0.34, p=0.001) and total cumulative testosterone dose (r=0.33, p=0.002) demonstrated significant positive correlations with maximum hematocrit. Among those developing erythrocytosis, time to elevation varied considerably across individuals.
Conclusions: Approximately one in eight transgender adolescents receiving injectable testosterone developed erythrocytosis. The 12.4% incidence aligns with adult transgender cohort data (11%) and supports current recommendations for ongoing hematocrit surveillance in this population. Longer treatment duration and higher cumulative dosing were associated with elevated hematocrit levels.
Erythrocytosis In Transgender Adolescents Receiving Injectable Testosterone: A Single-center Retrospective Cohort Study
Objectives: Erythrocytosis is a recognized complication of testosterone therapy, yet adolescent-specific safety data remain limited. We sought to determine the incidence of erythrocytosis and characterize hematocrit trajectories in transgender adolescents receiving injectable testosterone esters.
Methods: We conducted a retrospective chart review of transgender adolescents and young adults initiating gender-affirming testosterone therapy at a pediatric endocrinology referral center (2012-2021). Patients receiving injectable testosterone esters (cypionate or enanthate) for ≥3 months with serial hematocrit monitoring were included. The primary outcome was erythrocytosis, defined as hematocrit ≥50%. Pearson correlations assessed relationships between treatment duration, cumulative dose, and maximum hematocrit.
Results: Eighty-nine patients were included (median age 16.4 years, IQR 15.7-17.4). Median baseline hematocrit was 39.7% (IQR 38.5-42.3); no patients had elevated hematocrit at baseline. Mean treatment duration was 38.8 months (range 10-142). Erythrocytosis occurred in 11/89 patients (12.4%). Mean maximum hematocrit was 46.3% (SD 3.1). Both treatment duration (r=0.34, p=0.001) and total cumulative testosterone dose (r=0.33, p=0.002) demonstrated significant positive correlations with maximum hematocrit. Among those developing erythrocytosis, time to elevation varied considerably across individuals.
Conclusions: Approximately one in eight transgender adolescents receiving injectable testosterone developed erythrocytosis. The 12.4% incidence aligns with adult transgender cohort data (11%) and supports current recommendations for ongoing hematocrit surveillance in this population. Longer treatment duration and higher cumulative dosing were associated with elevated hematocrit levels.
Comments
Poster Board Number: 27