Revisiting Injectable Estrogen Dosing Recommendations for Gender-Affirming Hormone Therapy

Area of Science:

• Endocrinology
• Gender-affirming hormone therapy

Background:

• Injectable estrogens are recommended in guidelines for gender-affirming hormone therapy.
• Limited data exist for transgender and gender-diverse populations regarding injectable estrogen use.
• Concerns include assay variability and estradiol level fluctuations.

Purpose of the Study:

• To review current practices and guideline recommendations for injectable estrogen dosages.
• To identify trends in prescribed dosages and resulting serum estradiol levels.
• To provide recommendations for safe initiation of injectable estrogen therapy.

Main Methods:

• Review of existing guidelines for injectable estrogen therapy.
• Analysis of reported serum estradiol (E2) levels in transgender and gender-diverse patients.
• Assessment of prescribed intramuscular dosages of estradiol cypionate or valerate.

Main Results:

• Some patients receive high-dose injectable estrogen injections, leading to supraphysiologic serum E2 levels.
• Prescribed doses often exceed the recommended range for initiating therapy.
• Weekly doses of 5 mg or lower are suggested to prevent supra-physiological levels.

Conclusions:

• Initiating injectable estrogen therapy at 5 mg weekly or lower is recommended.
• Avoiding supraphysiologic estradiol levels is crucial for safe and effective gender-affirming care.
• Further research is needed to optimize injectable estrogen dosing for transgender and gender-diverse individuals.