Hormone Replacement Therapy and the Breast Cancer Risk
In 1991, the U.S. National Institute of Health (NIH), initiated a large-scale study, now infamously known as the Women’s Health Initiative (WHI).
The WHI consisted of clinical trials and observational research conducted to address major health issues in postmenopausal women. In its entirety, the WHI studied more than 160,000 postmenopausal women aged 50-79 years.
The trial itself was abrubtly ended early in 2002 when the researchers found that the subjects taking synthetic estrogen plus progestin had a greater incidence of coronary heart disease, breast cancer, stroke, and pulmonary embolism than the subjects receiving placebo only. In other words, the associated health risks of the combination conventional hormone replacement (HRT) were determined to outweigh the benefits. (Source)
In a study published in the New England Journal of Medicine, following the release of the 2002 report of the WHI trial, it noted that the WHI findings were the catalyst for the substantial decrease in HRT use by women in the United States. Not surprisingly, according to this study, the incidence of breast cancer also began to drop, suggesting a cause-and-effect relation between hormone treatment and breast cancer. The increased risk of breast cancer, among study participants alone, that were associated with the use of estrogen plus progestin, declined markedly soon after discontinuation of combined hormone therapy. (Source)
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Oral Contraceptives and the Breast Cancer Risk
Now, let’s take a minute to look at the breast cancer risk with regard to oral contraceptive use…
Like HRT, oral contraceptives are synthetic hormones; however, they are usually much more potent. Even the low dose birth control pill, that many women in their 40’s use as an inexpensive option to manage perimenopausal symptoms and to regulate cycles, is a stronger form of hormones then is usually given with standard HRT.
A meta-analysis published in the October 2006 issue of the Mayo Clinic Proceedings indicts oral contraceptives as putting premenopausal women at significantly increased risk for breast cancer, especially women who use them prior to having a child.
In 2003 the National Cancer Institute (NCI) found a substantially increased risk of several types of cancer amongst oral contraceptive users, citing a “significant increase” of the risk of breast cancer, as well as an increase in the risk of cervical and liver cancers. Despite this admission, no significant steps were taken to protect women’s health and to curb the use of combined oral contraceptive use.(Source)
In 2005, the International Agency for Research on Cancer (IARC), a division of the World Health Organization, officially classified oral contraceptives as a Group 1 carcinogen. The Group 1 classification is the highest classification of carcinogenicity, used only “when there is sufficient evidence of carcinogenicity in humans.”
Not surprisingly, both the Mayo Clinic and the WIH study were soon discredited by critics. Subsequently both the WIH and the Mayo Clinic ‘revised’ their findings, and their initial statements have been removed from their websites. However, the evidence is irrefutable, and new studies continue to come forth that show the clear link between synthetic hormones and breast cancer risk. (Source)
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Suits against Pfizer, the World’s Largest Drug Maker of Hormone Replacement Therapy (HRT)
By the end of 2011, Pfizer, the world’s largest drug maker, and its Wyeth and Pharmacia & Upjohn units were said to have resolved about 46% of lawsuits that claimed the companies’ hormone-replacement medicines, caused breast cancer.
More than 6 million women took Prempro (a combined estrogen & progesterone drug prescribed to treat menopausal symptoms) and related menopause drugs to treat symptoms including hot flashes and mood swings before the 2002 WIH study highlighted their links to cancer. Wyeth’s sales of the medicines, which are still on the market, exceeded $2 billion before the release of the Women’s Health Initiative study sponsored by the National Institutes of Health. (Source)
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Synthetic –versus- Bioidentical Hormones
Synthetic hormones are derived from plant and animal estrogens. Premarin, (an estrogen mixture) which the conventional health industry prescribes for estrogen replacement, is a concentrated mixture of chemicals derived from horse’s urine. Yep, that’s right – horse’s urine!
Provera, is the conventional health industry’s answer to replacing the natural progesterone that our body’s make; however, Provera is not progesterone!
Bioidentical hormones have been around for years, although most conventional physicians are not familiar with them, and many other physicians, who think they are (familiar with them), will tell you that synthetic hormones and bioidentical hormones are exactly the same because they are both created in a lab.
While it is true that bioidentical hormones, like synthetic hormones, are made in a lab, what is not true is that they are exactly the same. The difference lies in the molecular structure of the hormones.
Unlike chemically altered synthetic hormones, bioidentical hormones contain the same molecular structure as those produced naturally by your body. As a result, your body “recognizes” these hormones and interacts with them in the same way it would interact with the hormones produced in your ovaries – like a key fitting properly in a lock.
Bioidentical hormones are the key which fits perfectly into our body’s hormone receptors, the lock. Once in place, our bodies shift back into balance and all of those nasty symptoms of hormone imbalance begin to subside.
Synthetic hormones, on the other hand, have chemically altered shapes which are not recognized by your body. Furthermore, they are not metabolized efficiently in the body and interfere with the normal ebb and flow of hormonal function, potentially causing detrimental side effects. (Source)
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Are you a Candidate for Hormones? Is There a Recommended Dosage?
Every woman is different. One of the great dangers of years of prescribing synthetic hormones, was that the medical industry wrote out hormone prescriptions mostly without ever evaluating a woman’s hormone levels. It was a “one size fits all” fiasco.
Taking an excess amount of hormones, whether they be synthetic or bioidentical is dangerous. There is no one set dosage of progesterone or estrogen for any two women. In order to determine your body’s needs, a hormone panel needs to be taken at your practitioners office. We recommend a practitioner that has knowledge and experience with both conventionally prescribed synthetic hormones as well as bioidentical hormones. Ideally, hormone panels should be taken at least twice yearly, unless otherwise directed by your healthcare provider, and hormone treatments adjusted as necessary.
Patients report greater satisfaction with bioidentical HRTs that contain progesterone compared with those that contain a synthetic progestin. Bioidentical hormones have some distinctly different, potentially opposite, physiological effects compared with their synthetic counterparts, which have different chemical structures.
Physiological data and clinical outcomes demonstrate that bioidentical hormones are associated with lower risks, including the risk of breast cancer and cardiovascular disease, and are more efficacious than their synthetic and animal-derived counterparts. In fact, synthetic progestins have a variety of negative cardiovascular effects, which may be avoided with progesterone.Until evidence is found to the contrary, bioidentical hormones remain the preferred method of HRT. Further randomized controlled trials are needed to delineate these differences more clearly. (Source)
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According to, Dr John R. Lee, M.D , who was an international authority and pioneer in the use of natural progesterone cream and natural hormone balance, “The typical doctor if you ask "What is Provera", will say "Oh it is progesterone".
So progestin is the name of the artificial synthetic drug that is sold by the doctor thinking it is progesterone.... Real progesterone is the one made from plants. Doctors know that real progesterone must be used for invetro fertilizations – provera, synthetic progesterone, won't work.... Recent studies have also shown that progesterone protects against coronary spasms and post-menopausal heart attacks and provera does not provide this protection.” (Source)
- Dr John R. Lee, M.D
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