There is no single “best” estrogen for everyone. The answer depends on your age, health history, and what you’re treating. That said, 17-beta estradiol, the same molecule your ovaries naturally produce, is the most widely recommended form today. It comes in patches, gels, sprays, and pills, and it’s the foundation of most modern hormone therapy prescriptions for both menopause and gender-affirming care.
The bigger decision isn’t just which estrogen molecule to use. It’s how you take it. The delivery method, whether through your skin or swallowed as a pill, changes how the hormone moves through your body and what risks come with it.
Estradiol vs. Conjugated Estrogens
Two types of estrogen dominate prescriptions. The first is 17-beta estradiol, often just called estradiol. It’s chemically identical to the estrogen your body made before menopause, which is why it’s sometimes labeled “bioidentical.” The second is conjugated equine estrogens (brand name Premarin), a blend derived from horse urine that contains estradiol plus several other estrogen compounds not naturally found in humans.
Both effectively treat hot flashes, night sweats, and vaginal dryness. Both reduce fracture risk at all bone sites by 20 to 40 percent. The shift toward estradiol in recent years reflects a preference for using the exact hormone the human body recognizes, rather than a mix of horse-derived compounds. Most major medical guidelines now list estradiol as the preferred option, and conjugated estrogens are prescribed far less often than they were a decade ago.
Why the Delivery Method Matters More Than You Think
When you swallow an estrogen pill, it passes through your liver before reaching the rest of your body. This “first pass” through the liver triggers changes in clotting factors, triglycerides, and other proteins. When estrogen is absorbed through your skin via a patch, gel, or spray, it enters the bloodstream directly and skips the liver entirely.
That distinction has real consequences. A large study using UK medical databases found that oral estrogen was associated with a 58 percent increased risk of blood clots compared to not using hormone therapy. Transdermal estrogen showed no increased clot risk at all. When the two routes were compared head to head, oral estrogen carried a 70 percent higher clot risk than transdermal.
The metabolic differences go further. Oral estrogen raises triglycerides and shifts the ratio of estrogen types in your blood: the estrone-to-estradiol ratio becomes roughly five times higher than what’s normal before menopause. Transdermal estradiol keeps that ratio close to premenopausal levels. Oral estrogen also increased body fat content by about 12 percent in one study, while transdermal estrogen showed no significant change. Transdermal estrogen produces larger, more oxidation-resistant LDL particles, which may be better for cardiovascular health.
For these reasons, transdermal estradiol is increasingly considered the safer route, particularly for women over 40 or anyone with elevated risk for blood clots, high triglycerides, or cardiovascular disease.
Patches, Gels, and Sprays
Transdermal estradiol comes in several forms. Patches are the most common, accounting for about 87 percent of transdermal prescriptions. You apply a patch to your lower abdomen or hip once or twice a week, depending on the brand, and it delivers a steady dose through the skin. Gels come in pump dispensers or single-use sachets and are applied daily to the arm or thigh. Sprays work similarly.
Estradiol tablets come in 1 mg and 2 mg strengths and are taken once daily. You’ll typically start at the lowest dose that controls your symptoms. Your prescriber can adjust up if needed. There is no universal “right” dose; it depends on your symptoms, age, and response.
FDA-Approved vs. Compounded Hormones
You may have heard the term “bioidentical hormones” used to market custom-compounded products from specialty pharmacies. It’s worth understanding the distinction. FDA-approved bioidentical estradiol (sold under brand names like Estrace, Vivelle, Climara, and others) has been tested for safety, purity, and consistent dosing. These products are required to report side effects and carry standardized labeling.
Compounded bioidentical hormones are mixed by a pharmacist based on a prescription. They are not FDA-approved, not tested for safety or effectiveness, and the pharmacies that make them are not required to report side effects. Some compounded blends include additional hormones that haven’t been adequately tested. The Cleveland Clinic notes that the lack of required side-effect reporting contributes to the misconception that compounded hormones are safer, when in reality there’s simply less information available about their risks. If an FDA-approved version of your prescribed estrogen exists, it’s generally the more reliable choice.
When You Need Progesterone Too
If you still have your uterus, estrogen alone can thicken the uterine lining and increase the risk of endometrial cancer. That’s why prescribers pair estrogen with a progestogen (a progesterone-like medication) for anyone who hasn’t had a hysterectomy. If you’ve had a hysterectomy, estrogen alone is typically all you need.
This applies regardless of whether you use oral or transdermal estrogen, and regardless of the dose.
Timing and Age
The North American Menopause Society’s 2022 position statement draws a clear line. For women under 60 or within 10 years of menopause onset with no contraindications, the benefits of hormone therapy outweigh the risks for treating hot flashes and preventing bone loss. For women who start more than 10 years past menopause or after age 60, the balance shifts: absolute risks of heart disease, stroke, blood clots, and dementia increase.
If your only symptom is vaginal dryness or urinary discomfort, low-dose vaginal estrogen (a cream, ring, or tablet applied locally) is preferred over systemic therapy. These products deliver estrogen directly to the tissue that needs it, with minimal absorption into the bloodstream.
Estrogen for Gender-Affirming Care
For transfeminine individuals, estradiol is the clear standard. Oral estradiol, transdermal patches, and injectable estradiol valerate are all used, with target blood levels of 100 to 200 pg/mL. Ethinyl estradiol, a synthetic estrogen found in many birth control pills, is strongly recommended against for transgender patients due to elevated clot risk. After age 40, transdermal formulations are preferred for the same metabolic and clotting safety reasons that apply to menopausal therapy.
The Short Version
Estradiol delivered through the skin is the option with the strongest safety profile for most people. It matches what your body naturally produces, avoids liver metabolism, and carries no additional blood clot risk. Oral estradiol is a reasonable alternative when patches or gels aren’t practical, but it comes with trade-offs in clotting risk and metabolic effects. Conjugated equine estrogens still work but have largely fallen out of favor. Compounded hormones should be a last resort when an FDA-approved product isn’t available. Your starting dose, delivery method, and whether you need added progesterone all depend on your specific situation.