From the Guidelines
Transdermal 17β-estradiol is the preferred alternative estrogen therapy to conjugated estrogen (Premarin) due to its better safety profile and more beneficial effects on circulating lipids, markers of inflammation, and blood pressure. Several alternative estrogen therapies can be used instead of conjugated estrogen (Premarin) for patients requiring hormone therapy, including estradiol (available as oral tablets, transdermal patches, vaginal rings, or topical gels), estropipate (Ogen), and synthetic conjugated estrogens (Cenestin) 1. The appropriate dosing depends on the specific formulation and patient needs, with transdermal 17β-estradiol being a preferred route as it mimics physiological serum estradiol concentrations and avoids the hepatic first pass effect 1.
Some key points to consider when choosing an alternative estrogen therapy include:
- The patient's specific symptoms and risk factors
- Preferences regarding administration route
- Insurance coverage, as costs vary significantly between products
- The potential benefits of bioidentical estradiol, which may offer a more physiologic effect
- The advantages of transdermal options, which bypass first-pass liver metabolism and may reduce clotting risks 1
- The potential benefits of plant-derived options, which avoid animal products found in Premarin (derived from pregnant mare urine)
According to the most recent and highest quality study, transdermal 17β-estradiol has been demonstrated to be more effective in achieving a bone mineral density peak and reducing bone resorption markers compared to ethinylestradiol (EE)-based COC 1. Therefore, when considering alternative estrogen therapies, transdermal 17β-estradiol should be prioritized due to its superior safety profile and beneficial effects on various health outcomes.
From the Research
Alternative Estrogen Therapies
As a healthcare provider, you are looking for alternative estrogen therapies to conjugated estrogen (Premarin) for your patients. The following options can be considered:
- Transdermal Bioidentical Hormone Therapy: A study published in 2013 2 found that transdermal bioidentical hormone therapy, including estriol, estradiol, progesterone, DHEA, and testosterone, may offer a different risk/benefit profile compared to conventional hormone replacement therapy.
- Transdermal 17β-estradiol: A 14-year follow-up study of the Kronos Early Estrogen Prevention Study (KEEPS) found that transdermal 17β-estradiol (Climara, 50 μg/d) had similar cardiometabolic outcomes to oral conjugated equine estrogens (Premarin, 0.45 mg/d) 3.
- Oral Estradiol/Micronized Progesterone: A retrospective longitudinal study found that oral estradiol/micronized progesterone may be associated with a lower risk of venous thromboembolism compared to conjugated equine estrogens/medroxyprogesterone acetate 4.
Key Considerations
When considering alternative estrogen therapies, the following factors should be taken into account:
- Route of Delivery: Transdermal delivery may have a lower risk of venous thromboembolism and stroke compared to oral delivery 5, 6.
- Dose and Formulation: The dose and formulation of the hormone therapy can affect cardiometabolic markers and risks of clinical cardiovascular disease events 6.
- Individual Patient Factors: The patient's medical history, risk factors, and individual needs should be considered when selecting an alternative estrogen therapy.
Potential Benefits and Risks
The potential benefits and risks of alternative estrogen therapies should be carefully evaluated, including:
- Relief of Menopausal Symptoms: Alternative estrogen therapies may provide relief from menopausal symptoms, such as hot flashes and night sweats 2.
- Cardiovascular Risks: The risk of cardiovascular events, such as stroke and venous thromboembolism, should be carefully considered when selecting an alternative estrogen therapy 5, 4.