It bugs me. Baffles me. Befuddles me. Bemuses me. 

With all the information out there—online, magazines, TV shows—how is it that women experiencing hot flashes, vaginal dryness and other symptoms of menopause continue to take estrogen therapy?

There’s nothing necessarily wrong with hormone therapy in general. In my functional medicine practice, I’ve helped dozens of women transition gracefully into menopause with minimal symptoms. 

But I never, repeat, never never ever prescribe estrogen therapy only. In fact, I proscribe it. (Technically, “proscribe” means forbidden by law, but you get the point.) 

There’s lots of reasons why. Let me count the ways:

  • Increased risk of blood clots

    (Estrogen increases the production of certain proteins involved in blood clotting, such as clotting factors and fibrinogen. This can potentially lead to a more pro-coagulant state, making the blood more prone to clotting.)
  • Higher association with endometrial cancer – estrogen-only therapy can stimulate the growth of the uterus lining, says the Mayo Clinic.
  • Associated with a higher risk of breast cancer
  • May increase the chances of heart attack
  • Linked to dementia risk

So for this article, I want to focus on this last one. 

JAMA: Dementia in Women Using Estrogen-Only Therapy

A research letter from Dec. 18, 2023 published in the Journal of the American Medical Association Network (JAMA) investigated the association between estrogen-only hormone therapy and the risk of developing dementia in women who had undergone a hysterectomy. The research followed 29,104 women with hysterectomies and found that estrogen-only use was linked to an increased risk of dementia, even in women exposed to the therapy near menopause. 

The association persisted in women using estrogen-only therapy until a maximum age of 55 years.

This wasn’t the first study showing an association between dementia and estrogen-only therapy. Nor will it be last. To be clear, researchers aren’t 100% sure what the connection is between cognitive decline and estrogen-only replacement therapy; there is no causation; it’s just a speculative correlation. 

But there are theories that make total sense to me, and I’ll outline a few of them here…

Why Does Estrogen-Only Therapy Cause Cognitive Decline?

Hormonal Influence on Brain Function

Estrogen plays a role in various aspects of brain function, including synaptic activity, neurotransmitter regulation, and neuroprotection. Pretty important stuff in the noggin! When ladies go through menopause, their estrogen levels change. With estrogen-only therapy, there are no other hormones to balance out estrogen levels. So, it could be that too high estrogen levels may negatively affect brain function.

Timing and Duration of Hormone Therapy

Some studies suggest that starting hormone therapy near the onset of menopause might have different effects than starting it later. Personally, I don’t ever recommend estrogen-only therapy. No matter what your age. 

Vascular and Neuroprotective Effects

Hooray for estrogen! Estrogen is great! It’s got cardiovascular (heart, circulatory system) and neuroprotective (brain) effects. But disruptions to estrogen levels without balancing it out with other hormones (hey progesterone: I’m talking about you!) might be associated with an increased risk of cognitive decline.

When Should Women Start Hormone Replacement Therapy?

Let’s defer to the so-called experts at the Mayo Clinic. They state: 

“Women who begin hormone therapy at age 60 or older or more than 10 years from the onset of menopause are at greater risk of the above conditions [breast cancer, heart attack, etc.]. But if hormone therapy is started before the age of 60 or within 10 years of menopause, the benefits appear to outweigh the risks.”

I’m not saying I totally disagree with that. But what if you’re well into your late 50s or 60s and you’re a miserable wreck suffering from night sweats, hot flashes, zero libido, a vaginal tract that’s as dry as the Sahara? Then what? Should you just suffer because you’re at greater risk? 


The first step is getting a comprehensive hormone diagnostic test such as the DUTCH PLUS test. Then, based on your results, I will provide you with bioidentical hormone therapy that includes not only estrogen but also progesterone, which acts like a seesaw to estrogen to keep levels balanced. 

Synthetic vs Bioidentical Hormone Replacement

What sounds better to you? Taking a synthetic form of progesterone that comes from the urine of a pregnant horse or natural bioidentical estrogen derived from wild yam? I don’t know about you, but I’ll take door number two! Conjugated equine estrogen (CEE) is a form of estrogen hormone derived from pregnant mares’ urine and contains a mixture of various estrogens. It’s the most common estrogen replacement. 

But if you work with me, you’ll be able to support a healthy, balanced estrogen level using bioidentical hormones from wild yam; no horse pee necessary! Your estrogen levels will be ideally balanced because you’ll also take bioidentical progesterone. 

Ready to get hormonally balanced? 

The first step is setting an appointment here

Until next time, 

Jenna Witt
Nurse Practitioner (NP) and Functional Medicine Practitioner

Founder of Fundamental Wellness of Nebraska