What Is Bioidentical Hormone Replacement Therapy?

Hormones are chemicals made by the endocrine system. They direct functions in multiple systems of the body. When they are imbalanced, it can affect your weight, mood, energy levels, libido, fertility, and more. 

Hormone replacement therapy (HRT) is the use of artificial hormones to balance hormone levels and decrease symptoms. Bioidentical hormone replacement therapy (BHRT) is one version of this kind of treatment.

This article reviews what bioidentical hormones are, what BHRT treats, how it differs from other forms of HRT, its benefits and risks, and how to take it. 

birth control pills, the pill, HRT, hormone replacement therapy, estrogen, thyroid

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What Is Bioidentical Hormone Replacement Therapy?

Hormones control sexual health, mood, body temperature, growth, immunity (ability to fight infection), and more. Bioidentical hormone replacement therapy is a type of treatment used to reduce symptoms related to hormone imbalances

What Are Bioidentical Hormones?

Bioidentical hormones are synthetic (artificial) versions of the hormones already made in the endocrine system. They are chemically and structurally identical to human hormones. 

Bioidentical hormones are often confused with “natural” hormone therapy. "Natural hormones" is the term used to describe those extracted from plants such as yams and soybeans. 

Are Bioidentical Hormones Natural?

While parts of bioidentical hormones may be derived from natural sources, they are not considered natural because they are made in a lab.

What Can BHRT Treat?

BHRT can help with symptoms of imbalanced hormones, such as:

  • Mood swings 
  • Fatigue 
  • Difficulty concentrating 
  • Menopausal symptoms
  • Infertility (problems conceiving a baby)
  • Decreased libido (interest in sex)
  • Decreased risk of osteoporosis (postmenopause)
  • Temperature dysregulation

BHRT is also an important treatment for those who are transgender and are transitioning

Compounded Bioidentical Hormones vs. Standard BHRT

Standard BHRT is often confused with compounded bioidentical hormone replacement therapy (cBHRT). The following are the primary distinctions between standard BHRT and cBHRT: 

  • Standard BHRT is commercially available, prepackaged, standardized doses of bioidentical hormones approved by the Food and Drug Administration (FDA). 
  • Compounded BHRT involves custom compounded recipes mixed in a pharmacy. Formulas usually include a mixture of standard BHRT and nonhormonal ingredients; cBHRT is not FDA approved.

How to Take BHRT 

 BHRT comes in various forms and routes, including:

  • Oral capsules, tablets, or pills
  • Vaginal capsules
  • Lozenges
  • Oils (oral)
  • Topical (on the skin) creams, gels, solutions, or sprays
  • Transdermal (through the skin) patches
  • Suppositories (vaginal and rectal)
  • Enemas
  • Under-the-tongue pills, tablets, or drops (sublingual)
  • Nasal sprays
  • Under-the-skin implanted pellets 
  • Injections (shot)

Dosages and amounts vary based on the formulation and route of medication. It’s important to follow the prescriber's directions to get the most benefit from BHRT.

Transdermal HRT

There is strong scientific evidence that transdermal estrogen (a patch placed on the skin) decreases many risks associated with taking oral hormone therapy. The absorption is better, and it is less likely to cause side effects such as nausea. 

Traditional HRT vs. BHRT

The goal of hormone replacement therapy is to replace low levels of hormones. While levels may not be completely restored, treatment is usually enough to resolve symptoms. Differences between HRT and BHRT are:

  • Traditional HRT refers to synthetic hormones made in the lab. They are FDA-approved medications that come in standard, prepackaged doses. 
  • BHRT uses synthetic hormones that are the most identical to those in the body. They come in standard, commonly used doses that are approved by the FDA. The chemical structure of the hormones used in BHRT is often the same or similar as those used in traditional therapy. 

Benefits of BHRT

New studies have found that the benefits of HRT outweigh the risks for younger women or those in the early stages of menopause. BHRT has become a popular form of HRT over the last couple of decades. The perceived benefits of BHRT include:

  • Safety: Many healthcare providers and patients remain concerned about using HRT. Some feel BHRT is a safer alternative to traditional HRT. 
  • Customization: cBHRT can be mixed with standard BHRT to create a personalized dose based on your hormone levels, symptoms, and preference and is especially beneficial for those who are allergic to ingredients in standard BHRT or need a dose that is not available otherwise. 
  • They are exact duplicates: Bioidentical hormones are the most identical to those made in the body.

How Common Is Compounded BHRT?

An estimated 1 million to 2.5 million women in the United States use cBHRT for menopausal symptoms. 

Side Effects and Risks of BHRT

The side effects of BHRT vary depending on the type of hormone replacement used. Examples of side effects include:

  • Acne
  • Dyslipidemia (high cholesterol or triglycerides)
  • Mood swings
  • Hair loss
  • Breast tenderness
  • Weight gain
  • Fatigue
  • Bloating
  • Increased facial hair 
  • Itching in areas where topical medications are applied

As with any systemic (throughout the body) estrogen therapy, there is a slight risk of blood clots, breast cancer, and gallbladder disease. There is also a small risk of stroke and heart attack, especially for women over age 60.

For those who still have a uterus, there is also an increased risk for endometrial cancer.

Is Compounded BHRT Safer or More Effective?

While many people believe that cBHRT is safer or more effective than traditional HRT, this may not be true. According to the Endocrine Society, there is little to no scientific evidence to support these claims. 

There is concern that cBHRT does not have the FDA oversight needed to: 

  • Adequately test for safety and quality
  • Ensure doses are consistent 
  • Regulate effectiveness
  • Enforce labeling and packaging regulations (which can lead to allergic reactions and incorrect or incomplete information)

Summary

Bioidentical hormones are synthetic (artificial) hormones often confused with natural hormones derived from plants. Standard BHRT is tested, approved, and regulated by the FDA, while cBHRT is not. Many people prefer BHRT because of its perceived safety and because it can be customized. However, no scientific evidence shows they are safer or more effective than traditional HRT.

A Word From Verywell

Experiencing disruptions with your hormones can cause frustrating symptoms that interfere with your daily life. There are multiple options to help you combat these symptoms, including bioidentical hormone replacement therapy. Talk with your healthcare provider so they can help you decide on the best plan for your health and well-being.

Frequently Asked Questions

  • Is bioidentical hormone therapy safer and more effective than traditional hormone therapy?

    No, according to the FDA and the Endocrine Society, research has not shown that bioidentical hormones are safer or more effective than traditional hormones. 

  • Does bioidentical hormone replacement therapy (BHRT) really work?

    Standard BHRT that has been studied, approved, and regulated by the FDA is effective. However, compound bioidentical hormone therapy (cBHRT) is not FDA tested or approved. In addition, cBHRT dosages vary and there is insufficient evidence to know if they work correctly. 

  • How long can you stay on bioidentical hormones?

    How long you stay on bioidentical hormones varies based on the kind of hormone and your unique situation. For example, risk of adverse effects from systemic estrogen increases with age, especially for women over age 60, and with extended use (longer than 10 years). If your treatment stops working, you have severe side effects, or your risk increases, your healthcare provider may instruct you to discontinue hormone therapy. 

11 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. Borda L, Wong L, Tosti A. Bioidentical hormone therapy in menopause: Relevance in dermatology. Dermatol Online J. 2019;25(1):13030/qt4c20m28z. PMID: 30710894.

  2. Dalton-Brewer, N. The role of complementary and alternative medicine for the management of fibroids and associated symptomatology. Curr Obstet Gynecol Rep 5, 110–118 (2016). doi.org/10.1007/s13669-016-0156-0

  3. Stanczyk F, Matharu H, Winer S. Bioidentical hormones. Climacteric. 2021;24(1):38-45. doi: 10.1080/13697137.2020.1862079

  4. Endocrine Society. Compounded bioidentical hormone therapy.

  5. Files J, Kransdorf L, Ko M, et al. Bioidentical hormone therapy: An assessment of provider knowledge. Maturitas. 2016;94:46-51. doi: 10.1016/j.maturitas.2016.08.014

  6. National Academies of Sciences, Engineering, and Medicine. The clinical utility of compounded bioidentical hormone therapy: A review of safety, effectiveness, and use.

  7. Newson L, Lass A. Effectiveness of transdermal oestradiol and natural micronised progesterone for menopausal symptoms. British Journal of General Practice. 2018;68(675):499-500. doi: 10.3399/bjgp18X699353

  8. Dubaut J, Dong F, Tjaden B, Grainger D, Duong J, Tatpati L. Prescribing bioidentical menopausal hormone therapy: A survey of physician views and practices. J Womens Health (Larchmt). 2018;27(7):859-866. doi: 10.1089/jwh.2017.6637

  9. Abou-Ismail MY, Citla Sridhar D, Nayak L. Estrogen and thrombosis: A bench to bedside review. Thromb Res. 2020;192:40-51. doi: 10.1016/j.thromres.2020.05.008

  10. United States (U.S.) Food & Drug Administration. Menopause & hormones: Common questions.

  11. Cagnacci A, Venier M. The controversial history of hormone replacement therapy. Medicina (Kaunas). 2019;55(9):602. doi:10.3390/medicina55090602

By Brandi Jones, MSN-ED RN-BC
Brandi is a nurse and the owner of Brandi Jones LLC. She specializes in health and wellness writing including blogs, articles, and education.