Biest, Bioidentical hormone replacement therapy, Menopause symptom management Transdermal estradiol and progesterone, Safer hormone replacement

Menopause is a natural transition in a woman's life that can bring about various symptoms due to hormonal changes. Hormone replacement therapy (HRT) has been a cornerstone in managing these symptoms, but not all HRT is created equal. BIEST, a bioidentical hormone preparation combining estradiol and estriol, offers a tailored approach that may provide superior symptom relief with a potentially better safety profile.

Transdermal Estradiol and Progesterone: A Safer Postmenopausal HRT

Transdermal administration of estradiol, particularly when combined with natural progesterone, is emerging as a safer alternative to traditional forms of HRT. This method bypasses the first-pass hepatic effect, potentially reducing the risk of venous thromboembolism and possibly breast cancer11718. The transdermal route delivers hormones directly into the bloodstream, minimizing the impact on the liver and reducing the risk of clotting and other cardiovascular events.

Breast Cancer Risk with Different HRTs

The type of HRT significantly affects breast cancer risk. Estrogen-progestagen combinations, especially those involving synthetic progestins, are associated with a higher risk compared to estrogen-only therapy. The choice of progestagen is crucial, with natural progesterone or dydrogesterone potentially offering a safer profile regarding breast cancer risk2578.

Bioidentical Hormones: Safety and Efficacy

Bioidentical hormones, including estradiol, estriol, and progesterone, are argued to be safer and more efficacious than synthetic and animal-derived counterparts. Patients often report greater satisfaction with bioidentical hormones. Physiological data suggest potential lower risks, including for breast cancer and cardiovascular disease. However, conclusive evidence from randomized controlled trials is still needed to confirm these claims391920.

Menopausal Symptom Management and Cardiovascular Risk

HRT is the most effective treatment for managing menopausal symptoms. The route of estrogen administration (oral vs. transdermal) and the type of progestogen used can significantly impact the risk profile of HRT, particularly concerning cardiovascular disease and venous thromboembolism. Transdermal routes and natural progesterone may offer advantages in safety416.

Advantages of BIEST Over Estradiol Alone

BIEST offers several potential benefits over estradiol alone:

  • Balanced Hormonal Effects: Estriol can balance the stronger effects of estradiol, potentially reducing the risk of side effects associated with high levels of estradiol.
  • Customizable Ratios: BIEST can be compounded in various ratios of estriol to estradiol, allowing for personalized treatment plans based on individual symptoms, goals, and safety profiles.
  • Potential for Reduced Risks: Some studies suggest that estriol may have a less stimulatory effect on breast and endometrial tissue, which could translate to a lower risk of certain cancers.

Clinical Evidence Supporting BIEST

Research indicates that different hormone therapy doses, formulations, and routes of delivery, including transdermal estrogen, do not appreciably differ in invasive breast cancer risk compared to conventional oral conjugated equine estrogens (CEE), supporting the safety profile of transdermal BIEST as an alternative to traditional estrogen therapies11718.

Personal Clinical Observations with BIEST

In my practice, women previously treated with estradiol alone who experienced persistent menopausal symptoms have shown remarkable improvement once switched to BIEST. The addition of estriol provides a more comprehensive relief, underscoring the potential of this therapy to offer superior symptom relief for women during menopause and perimenopause.


BIEST represents a tailored approach to bioidentical hormone replacement therapy, offering the benefits of estradiol while potentially mitigating its risks through the addition of estriol. Its customizable nature allows healthcare providers to fine-tune treatment to the individual needs of their patients. If you are experiencing menopausal or perimenopausal symptoms and are interested in exploring whether BIEST could be right for you, I invite you to make an appointment with me. Together, we can discuss your symptoms, treatment goals, and whether BIEST hormone replacement therapy could offer you relief and improve your quality of life.


Dr. Anat Sapan MD, specializing in peri/menopause care, advocates for a personalized approach combining Bioidentical Hormone Replacement Therapy with lifestyle strategies. Her telemedicine services in California, Florida and Illinois aim to help women overcome menopausal symptoms and enhance their quality of life.

Anat Sapan, MD

Anat Sapan, MD

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