Bioidentical Hormone Therapy in Postmenopausal Women: What It Is and How It May Help Blood Sugar

Menopause changes more than hot flashes and sleep—it also affects how your body handles sugar and insulin. In this post, we’ll break down what bioidentical hormones are, how the drop in estrogen after menopause can raise diabetes risk, and what the research says about bioidentical hormone therapy (BHRT) and glucose control.

What are “bioidentical” hormones?

Bioidentical hormones are hormones that have the same chemical structure as the ones your body makes—most commonly estradiol (E2) and micronized progesterone. They’re available as FDA-approved products (patches, gels, sprays, pills, vaginal forms) and also as custom-compounded preparations. Medical societies emphasize that FDA-approved bioidentical options exist and should be preferred when possible because they’re standardized for dose and purity. (ACOG, The Menopause Society)

What happens to glucose and insulin after estrogen drops?

After menopause, estradiol levels fall. That drop can:

• Lower insulin sensitivity in muscle, liver, and fat tissue

• Increase visceral (abdominal) fat and low-grade inflammation

• Alter glucose production in the liver

Together, these shifts make it easier for blood sugar and fasting insulin to rise, which helps explain why the risk of type 2 diabetes climbs after menopause. Mechanistic and clinical reviews consistently describe estrogen as protective for insulin action and glucose balance. (ajp.amjpathol.org, PMC)

Can BHRT help with blood sugar?

1) Lower chance of developing diabetes

Large randomized trials from the Women’s Health Initiative (WHI) found that women assigned to menopausal hormone therapy had significantly lower rates of treated diabetes compared with placebo. (PMC)

2) Better insulin resistance (HOMA-IR)

Systematic reviews and meta-analyses show hormone therapy can reduce insulin resistance in postmenopausal women, with some evidence that estrogen-alone regimens produce larger improvements than combined regimens. Both oral and transdermal routes have shown benefits. (PubMed, The Menopause Society)

3) Improved glucose measures in women who already have diabetes

A 2023 analysis in Diabetes Care reported that postmenopausal hormone therapy reduced HbA1c in women with type 2 diabetes, indicating better average blood sugar control. (Diabetes Journals)

Important nuance: Some older studies suggest certain synthetic progestins (e.g., norethisterone acetate) may blunt estradiol’s insulin-sensitizing effect, whereas transdermal estradiol and micronized progesterone appear more metabolically neutral in many women. Choice of formulation and route matters. (Metabolism)

How might BHRT do this?

Estrogen acts through estrogen receptors in muscle, fat, liver, pancreas, and the brain. It can:

• Enhance muscle glucose uptake

• Reduce hepatic glucose output

• Improve adipose tissue signaling and reduce inflammation

• Support healthier fat distribution (less visceral fat)

These mechanisms align with the clinical benefits seen in trials and reviews. (ajp.amjpathol.org)

Practical considerations (safety & personalization)

• Best candidates: Generally healthy women within 10 years of menopause who have bothersome symptoms and no contraindications. This is also when metabolic benefits are most plausible. (The Menopause Society)

• Route matters: Transdermal estradiol (patch/gel/spray) avoids first-pass liver metabolism and is associated with a more favorable cardiometabolic risk profile in many observational analyses. (AHA Journals)

• Progesterone choice: If you have a uterus, pair estrogen with a progestogen to protect the lining. Many clinicians favor micronized progesterone for a more neutral metabolic profile. (The Menopause Society)

• Not a stand-alone diabetes treatment: BHRT can complement—not replace—nutrition, exercise, sleep, stress management, and standard diabetes therapies.

• Risks exist: As with any hormone therapy, consider VTE, breast, and gallbladder risks, and personalize to your history. WHI provides the largest randomized data on benefits and risks across outcomes. (PMC)

Bottom line

For appropriately selected postmenopausal women, bioidentical hormone therapy may improve insulin resistance and lower diabetes risk, with evidence strongest for those closer to menopause. Use BHRT as part of a comprehensive plan that prioritizes lifestyle and cardiometabolic risk reduction.

References

1. Manson JAE, et al. The Women’s Health Initiative Hormone Therapy Trials. Am J Epidemiol. 2013. (Lower rates of treated diabetes in HT groups.) (PMC)

2. Mauvais-Jarvis F. Menopausal Hormone Therapy and Type 2 Diabetes Prevention. Endocrine Reviews. 2017. (How estrogen influences glucose and diabetes risk; synthesis of RCTs.) (Academic Oxford)

3. Yan H, et al. Estrogen improves insulin sensitivity and suppresses hepatic glucose production. Front Endocrinol. 2018. (Mechanisms and clinical signals.) (PMC)

4. Li T, et al. Hormone therapy and insulin resistance in non-diabetic postmenopausal women: Meta-analysis. Menopause. 2024. (HT lowers HOMA-IR; estrogen-alone greater effect.) (PubMed)

5. The Menopause Society (NAMS). Hormone Therapy Position Statement. 2022. (Definitions; clinical guidance; bioidentical options.) (The Menopause Society)

6. ACOG Clinical Consensus. Compounded Bioidentical Menopausal Hormone Therapy. 2023. (Definition of bioidentical; FDA-approved vs compounded.) (ACOG)

7. Diabetes Care 2023. Effect of Postmenopausal HT on HbA1c in women with T2D: Meta-analysis. (HT reduced HbA1c.) (Diabetes Journals)

8. Spencer CP, et al. Oral vs transdermal estradiol; addition of norethisterone and insulin sensitivity. Metabolism. 2000. (Progestin can attenuate benefit.) (Metabolism)

9. Cho L, et al. Rethinking Menopausal Hormone Therapy: cardiometabolic considerations. Circulation. 2023. (Transdermal risk profile discussion.) (AHA Journals)

10. NAMS patient education page. What are bioidentical hormones? (Patient-friendly definition.) (The Menopause Society)

If you’d like, I can format this into a branded blog post for your site (title image, pull-quotes, CTA for consults, and an FAQ section about BHRT + diabetes).