Is Hormone Replacement Therapy (HRT) Safe?

In 2001, a clinical study named the Women’s Health Initiative (WHI) was stopped short because estrogen use was found to be associated with increased breast cancer risk and heart disease.  Almost overnight, middle-aged women across America immediately tossed their hormone prescriptions into the trash or toilet and have been suffering unnecessarily ever since.

Interestingly, a recent Time magazine article, twelve years after the fact, suggested that researchers were now having second thoughts about the study; that in certain populations, hormone replacement therapy (HRT) might not be such a bad idea.

The HRT pendulum swings started back in the 1980’s, when I was in medical school.  At my institution, Wake Forest University, landmark research was being done on the topic.  Monkeys were given either placebo or conjugated equine estrogens (Premarin) with synthetic progesterone and were monitored.  At the end of life, autopsy was done to evaluate coronary artery disease.  The hormone replacement group had remarkably lower arterial plaque formation, and after the study was published, the entire medical community jumped on the Premarin bandwagon.  All postmenopausal women were strongly encouraged to take Premarin.

I came out of Ob/Gyn training writing prescriptions for Premarin like everyone else, but immediately noticed that Premarin caused extreme breast tenderness in more than half of my patients. This couldn’t be good. About the same time, clinical studies using Premarin in patients who had already had a heart attack were showing increased risk of having another heart attack, instead of decreased risk as was expected. Hmm.

I started switching all my patients to bioidentical HRT, using bioidentical (identical to human hormones) estrogens and progesterone.  It made logical sense and the results were fantastic; symptoms of hot flashes, night sweats, decreased libido and vaginal dryness were all controlled and breast tenderness was not a problem.

By the time the WHI study came out, I was not writing for Premarin or similar estrogen products and using bioidentical products exclusively. I was also paying better attention.  Science, if not guided by logical questions, can lead to very erroneous conclusions.

Estrogen, it turns out, has a dual effect on the cardiovascular system.  It lowers cholesterol and also has a direct protective effect on blood vessels.  At the same time, it increases coagulation (makes blood clot).  If given to patients with clean vessels (early menopause), the overall effect is protective.  If given to patients with established plaque formation, however, the overall effect is detrimental and risk is increased.

In this light, giving Premarin to patients with a previous heart attack was hugely flawed.

The same mistake was made in the WHI study.  It was designed to answer the question of whether estrogen protects against heart disease once and for all.  It was a huge double-blinded controlled study (considered the best and most definitive type of study).  Double-blinded controlled means that the drug in question was used in one group and placebo in another equal group of people, but no one knows who is getting what. Interestingly, however, using that particular study design was the source of the flaw.

Researchers were well aware that menopausal patients receiving placebo would stand out with symptoms; and therefore, symptomatic menopausal patients were removed from the study.  Amazing….the entire population of people who were the best candidates for HRT were largely absent from the study!

The study was comprised mostly of elderly patients (average age in the study was 63) who were using estrogen for the first time in their lives! Considering the dual nature of estrogen, seeing increased incidence of cardiovascular events in this at-risk population should not have been a surprise.

Reading the study for the first time, I was amazed that it had actually been conducted.  It did provide information, but not the information the researchers had been seeking.  It did not change, but rather supported, the counseling that I was giving patients at the time. The fact the Premarin increased risk of cardiovascular disease in elderly at-risk women and also increased risk of breast cancer was not a surprise to me.

It shouldn’t take science to conclude that horse estrogens (which are not well metabolized in the human body) that have been synthetically conjugated (a process to increase potency) might adversely affect risk of breast cancer.

At the other end of the spectrum, anti-aging practitioners are using hormone testing to load postmenopausal women (of any age) with bioidentical hormones to the level of a thirty year old…with no science to back it up. This may be just as hazardous as giving Premarin.

The right answer to HRT, as with most things, is somewhere in the middle.  In my practice I primarily use HRT with bioidentical estrogens and progesterone, but at the lowest possible dose to reduce symptoms and support bone and skin health.  Transdermal (skin application) is best for bypassing the liver and reducing effect on coagulation.

I primarily reserve HRT for early menopausal women who do not have risk factors for cardiovascular disease.  I have had great success complementing HRT with herbal therapy.  Herbs called adaptogens balance central hormone pathways and reduce symptoms.  This allows for controlling symptoms with low doses of HRT and very minimal risk.

Science is only as good as the questions asked; if common sense is not guiding the questions, then expect erroneous results!

Reprinted with permission from

Bill Rawls, MD is an advocate for individuals with fibromyalgia and related conditions. Board certified in Obstetrics and Gynecology, Dr. Rawls has always focused his practice on health and wellness. After experiencing fibromyalgia and Lyme disease first hand, he shifted toward helping others with those conditions. He uses his passions for writing and study of natural herbal medicine to reach out to those left behind by the current healthcare system. Through books and health restoration protocols available through Vital Plan, he paves the way toward a better life. His latest book, Suffered Long Enough, puts the pieces together for fibromyalgia and Lyme disease sufferers and offers a safe pathway back to normal health.

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