Iwamoto, Sean J

Injectable estrogens are options for gender-affirming hormone therapy per guidelines, which suggest intramuscular dosages of 5–30 mg every 2 weeks or 2–10 mg weekly with estradiol cypionate or valerate interchangeably. Data among transgender and gender-diverse patients are limited due to local unavailability and concerns around laboratory assay variability and estradiol (E2) level fluctuation. We note a concerning trend where patients are prescribed high-dose injections based on the guidelines leading to serum E2 levels well above the range recommended in the same guidelines. Our review indicates that 5 mg weekly or lower should be prescribed when initiating injectable estrogens to avoid supraphysiologic E2 levels.