Estradiol, explained and then priced

Estradiol is the main form of estrogen the ovaries produce during the reproductive years, and the hormone most menopause therapy replaces. It circulates and acts on receptors throughout the body, including bone, blood vessels, brain and the urogenital tract, which is why falling estradiol produces symptoms in so many unrelated-seeming places at once. Estradiol and estrogen are not synonyms: estrogen is the class, and estradiol is the specific molecule within it, alongside estrone and estriol. Prescription estradiol is chemically identical to what the body makes, which is what the word bioidentical means, and it is available as an FDA-approved product in pill, patch, gel, spray, cream and vaginal forms.

Estrogen is a group of hormones and estradiol is one member of it. The three that matter clinically are estradiol, the dominant form before menopause; estrone, which becomes the dominant form after it; and estriol, which is dominant during pregnancy. When a prescription says estradiol it means that specific molecule. When a product says estrogen it may mean estradiol, or it may mean conjugated equine estrogens, the Premarin-era preparation derived from horse urine, which is a different substance with a different profile.

Across the 5 women's-wing platforms we price-verify, the cheapest published systemic estradiol is Winona's tablets at $54 per 28-day cycle, all-inclusive. The same product in patch form costs nearly three times that on the same platform, $149 per 28-day cycle, which is the clearest illustration on our roster that the route is what you are paying for. Vaginal estradiol is the cheapest route of all where it is appropriate, with Wisp publishing a cream from $20. Form and price should not be the deciding factor on their own, because the route changes how the drug is metabolised.

Route matters for at least one outcome. Estradiol taken by mouth passes through the liver before reaching general circulation, and transdermal estradiol does not. That difference in first-pass metabolism is the mechanism behind the observed difference in venous thromboembolism risk between oral and transdermal estrogen reported in the BMJ 2019 nested case-control study. Vaginal estradiol prescribed for local symptoms is dosed far lower than systemic therapy and is generally considered separately.