Bioidentical Hormones: What That Term Actually Means

Medically reviewed by Ellen Byars, MSN, WHNP, MSCP · Written by Carrie Madormo, RN, MPH · September 11, 2026

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Key Takeaways

Bioidentical hormones are medications that share the same chemical and molecular structure as hormones the body naturally makes, and they come in two very different forms: FDA-approved products and compounded products.
FDA-approved bioidentical hormone therapy is tested and monitored for safety, comes in standard doses, and includes clear labeling about risks and benefits, while compounded versions skip that review process and can vary in strength from batch to batch. Some marketing claims about compounded hormones, like being safer than traditional hormone therapy or being customized through hormone testing, are not backed by reliable evidence.
If you are thinking about any type of hormone therapy for menopause symptoms, talking with your doctor or healthcare provider is an important first step to understanding which option may be right for your personal health history and needs.

If you’re overwhelmed by all of your hormone replacement therapy (HRT) choices, you aren’t alone. One type of treatment that’s been getting plenty of buzz is bioidentical hormone therapy.

In this article, we’ll cover what bioidentical hormones are, how they’re regulated, and what the benefits and risks are. We’ll also discuss how to tell the difference between products that have been reviewed for safety and effectiveness and those that haven’t.

🗳️ Have you tried bioidentical hormone therapy for menopause symptoms?

Yes, and it helped.

Yes, but it didn’t help.

No, but I’m interested.

No, and I’m not interested.

What Are Bioidentical Hormones?

Bioidentical hormones are medications that share the same chemical and molecular structure as hormones made by the body. The term “bioidentical” is a marketing term rather than a medical one.

There are two main categories, and it’s critical to understand the difference between them.

FDA-approved Bioidentical Hormone Therapy

This therapy uses precise duplicates of hormones like estrogen and progesterone, and these products are tested, approved, and monitored for safety by the FDA. FDA-approved hormone therapy products containing estradiol, estrone, or micronized progesterone meet the commonly used definition of bioidentical, and they come with package inserts that clearly state the possible risks and benefits.

Compounded Bioidentical Hormone Therapy

This therapy is prepared by a compounding pharmacist using a doctor’s prescription and does not undergo the same FDA approval and standardized safety and effectiveness review as FDA-approved products. It’s unclear how these products are absorbed by the body and how much they affect hormone levels. They can contain several different hormones, including estradiol, estrone, progesterone, and testosterone, and the specific combinations used have not been tested or approved.

FDA-Approved vs. Compounded Bioidentical Hormone Therapy

Calling both FDA-approved and compounded hormone therapies by the same name — bioidentical — is confusing and can be misleading. Three practical differences matter most:

FDA oversight — FDA-approved bioidentical hormone therapy is reviewed and monitored by the FDA, while compounded products are not.
Dosing — FDA-approved products are assessed for purity and potency and come in standard doses, so you know how much medication you’re taking, while compounded doses can vary widely.
Hormone testing — Compounded products are often dosed based on hormone levels measured in serum, saliva, or urine, but those tests haven’t been proven to be accurate or reliable.

The North American Menopause Society (now The Menopause Society) released a position statement in 2022 recommending that clinicians avoid prescribing compounded hormones unless a patient has serious allergies to FDA-approved hormones or their ingredients.

Quality, Dosing, and Safety Oversight

Compounded products do not have the same standardized labeling, premarket review, and safety evidence as FDA-approved products. That leaves three gaps:

Evidence — There aren’t enough quality studies to establish that compounded products are safe or effective.
Labeling — Most medications must include a package insert listing potential risks, but most compounded medications don’t.
Consistency — Because compounded products are prepared individually, the amount of hormone they contain may vary from batch to batch.

Benefits and Risks: How Bioidentical Hormones Behave in the Body

Hormone therapy is used to treat certain menopause symptoms that are severe enough to disrupt daily life. FDA-approved bioidentical hormone therapy may be an effective treatment for:

Hot flashes
Night sweats
Vaginal dryness
Pain with sexual intercourse
Mood changes

Hormone therapy is available in two forms:

Systemic hormones — These are absorbed throughout the body and come as oral pills, skin patches, gels, or sprays.
Local, vaginal hormones — These are absorbed mostly by vaginal tissue and come as creams, rings, and tablets.

Like traditional hormone therapy, FDA-approved bioidentical hormones are available as estrogen-only products or as a combination of estrogen and a progestogen. If you have a uterus, systemic estrogen is prescribed together with a progestogen to protect the uterine lining. (For background, see our guide to estrogen and progesterone.)

Women who are younger than 60 and within 10 years of their last period are at the lowest risk of experiencing a serious adverse event from hormone therapy.

Like any medical treatment, bioidentical hormone therapy has risks. It may not be safe for you if you have a history of:

Hormone-sensitive cancer
Blood clots
Stroke
Heart attack
Abnormal vaginal bleeding
Liver disease
Gallbladder disease

With a compounded bioidentical hormone product, the amount may not be consistent with the prescribed dose. This can put you at serious risk in two ways:

Too little progestogen — Taking systemic estrogen without an adequate amount of progestogen may cause your uterine lining to thicken, raising your risk of endometrial cancer.
Too much estrogen — If your estrogen levels become too high, you could be at risk of cancers of the breast and uterus, as well as serious complications, including blood clots.

Learn more on the different forms: Estrogen for Menopause: Creams, Patches, Pills, and More. ❯

Red Flags in Bioidentical Hormone Marketing

A few marketing claims deserve extra scrutiny:

“Safer than traditional hormone therapy” — There’s no evidence to support this claim, and most menopause societies and experts recommend avoiding compounded bioidentical hormone therapy.
Hormone testing to “customize” your dose — Many prescribers rely on serum and saliva hormone tests to determine your dose, but these tests have not been found to reliably measure your hormone levels.
Benefits borrowed from other research — Some makers of compounded hormones use study results from FDA-approved hormone therapy when making statements about possible benefits of their own products.

If you’ve been considering compounded hormones, talk with your doctor first. It’s crucial to understand the risks before deciding which type of hormone therapy is best for you.

References

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