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Published on: June 7, 2012
Sublingual Estradiol Is Associated with Higher Estrone Concentrations than Transdermal or Injectable Preparations in
Lauren R Cirrincione1, Gabrielle Winston McPherson2, Jessica Rongitsch3
1Department of Pharmacy, University of Washington, Seattle, Washington, USA.
Serum estrone levels were higher with sublingual estradiol compared to transdermal or injectable forms in feminizing gender-affirming hormone therapy (GAHT). Estradiol levels varied by injection versus transdermal methods but not with sublingual use.
Area of Science:
- Endocrinology
- Pharmacology
- Gender-affirming care
Background:
- Serum hormone profiles in feminizing gender-affirming hormone therapies (GAHT) are not well-characterized.
- Understanding estrogen levels is crucial for optimizing GAHT efficacy and safety.
Purpose of the Study:
- To characterize serum estrogen profiles (estrone and estradiol) for different 17β-estradiol formulations (sublingual, transdermal, injectable) used in feminizing GAHT.
- To investigate the association between estrone levels and estradiol concentration ranges or antiandrogen use.
Main Methods:
- Secondary analysis of a prospective cross-sectional study involving 93 transgender women and gender nonbinary adults on feminizing GAHT for ≥12 months.
- Utilized a novel liquid chromatography-mass spectrometry (LC-MS/MS) assay to measure serum estrone and estradiol concentrations.
- Compared hormone levels across different 17β-estradiol preparations (sublingual, transdermal, injectable) with or without spironolactone.
Main Results:
- Higher estrone concentrations were observed with sublingual 17β-estradiol compared to transdermal or injectable forms (p < 0.0001).
- Injectable 17β-estradiol yielded higher concentrations than transdermal (p = 0.0201), with both similar to sublingual.
- Higher estradiol levels (>200 pg/mL) correlated with higher estrone in sublingual users, but not in transdermal or injectable users. Spironolactone showed no association with estrone levels.
Conclusions:
- Sublingual 17β-estradiol administration results in higher serum estrone concentrations compared to transdermal or injectable formulations in individuals undergoing feminizing GAHT.
- The clinical significance of elevated estrone with sublingual estradiol and the impact of other antiandrogens require further investigation.
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