(Bioidentical vs. Synthetic)
Kent Holtorf, M.D.

Below is a summary of the risks and benefits of the various types of estrogen and progesterone replacement for women in menopause.

The benefits of estrogen replacement are very significant. It will not only relieve the symptoms that frequently accompany menopause, including hot flashes, irritability, insomnia, loss of sex drive, vaginal dryness, dry skin, sagging breasts, depression, and decreased memory, but it can also decrease the risk of stroke and heart attack by 50%, reduce the risk of broken bones from osteoporosis by 50%, reduce the risk of Alzheimer’s by 80%, reduce the risk of osteoarthritis by 40%, reduced the risk of periodontal disease and tooth loss by 40%, and reduce the risk of colon cancer by 30%. It can significantly reduce wrinkles and the signs of aging. Studies show that women who use estrogen replacement look younger then their age, and women who do not use estrogen after menopause look older than their age.

Synthetic progestins (Provera) when taken with estrogen have been shown to negate many of the beneficial effects of estrogen and significantly increase the risk of breast cancer, stroke and heart attack. These risks were verified in the recent Women’s Health Initiative (WHI) Study. The study was halted prematurely for those taking the progestin because of the increased risk of breast cancer, stroke and heart attack. The study was not halted for those who were not on synthetic progestins. Natural progesterone has no such negative effects and has been shown to add to estrogen’s benefits. This means that if you take Provera with your estrogen, you will not receive a large portion of the potential benefits of estrogen and put yourself at significant risk. Synthetic progestins such as Provera are associated with increased risk of heart attack, stroke, breast cancer, fatigue, depression, decreased exercise tolerance and coronary artery constriction, while natural progesterone exhibit no such problems. Natural progesterone protects against breast and uterine cancer, improves blood flow to the heart, augments estrogen’s positive effects on mood and helps to form new bone (estrogen alone only slows bone loss).

What about the risk of breast cancer?
The overall evidence from the research literature indicates that estrogens do not increase the risk of aggressive breast cancer, and that estrogen will decreases the mortality of breast cancer (users of estrogen replacement are less likely to die from breast cancer). When a synthetic progestin (Provera) is added to the estrogen, some studies show a decreased risk of breast cancer verses non-hormone replacement users while others show an increased risk, including the recent WHI Study. In contrast, natural progesterone is shown to have a strong protective effect against breast and other cancers. One study found that woman with adequate progesterone levels were 10 times less likely to die from cancer than women with low progesterone levels. Women with low progesterone are up to 10 times more likely to develop cancer and 5 times more likely to develop breast cancer. Natural progesterone has strong anti-cancer effects while synthetic progestins are carcinogenic. There is no study that shows that giving natural estrogens (even unopposed without progesterone) increases the risk of breast cancer. On the contrary, a woman taking natural estrogen and natural progesterone is provided protection against breast cancer, and she is at less risk of developing cancer when compared to women who are not on any hormone replacement therapy.

What is the ideal type of estrogen?
The ideal estrogen replacement is one that contains natural estradiol and estriol for maximal cancer protection and benefit, and is given transdermally (through the skin). This combination should always be given with natural progesterone.

Premarin, the most popular estrogen replacement therapy (ERT) and used in the recent WHI Study, is derived from pregnant horses and contains mostly estrone and a number of equine (horse) estrogens that are not natural to humans. Many of these foreign estrogens bind very tightly to the human estrogen receptors, making them highly stimulating and carcinogenic. Estrace, another popular form of estrogen is 100% estradiol. Estriol and natural progesterone should be added for maximum cancer protection.

In addition, a women’s testosterone level also declines with menopause, especially after a hysterectomy. Low testosterone will cause depression, fatigue, weight gain, low sex drive, and promote osteoporosis. Supplementation of testosterone to optimal levels can bring back that feeling of well-being and is very effective at reversing osteoporosis.

Common Questions

Why have I been told that I should not take progesterone if I had a hysterectomy?
Because synthetic progestins (Provera) have a negative impact on the body, they are not recommended unless absolutely necessary (as to protect against uterine cancer). Unopposed estrogen (without progesterone) does have significant risks including: increasing the risk of blood clots, fluid retention, promoting fat synthesis and increasing the risk of breast cancer. Progesterone, as opposed to synthetic progestins, has beneficial effects as listed above, including a decreased risk of breast cancer. There are progesterone receptors in all tissues of the body, and it has beneficial effects on these tissues, which include the heart, the bones and the brain. Natural progesterone should always be given along with estrogen replacement.

Should I take hormonal replacement therapy?
If so, what type? For most women, with the right hormones, the benefits outweigh any risks. In most cases, whether you have had a hysterectomy or not, your estrogen and progesterone levels should be optimized with replacement therapy. The estrogen replacement should contain a combination of transdermal estradiol for maximal benefit, estriol for protection against breast cancer, and natural progesterone to balance the estrogen and for its added benefits, which includes reversal of osteoporosis, and additional protection against breast cancer. The addition of small amount of testosterone can usually add benefits, as well, including increased sex drive, feeling of well-being and reversal of osteoporosis.

I take Premarin, is it OK?
Premarin, especially when given orally, can increase the risk of stroke, heart attack, and breast cancer. This is especially true if a synthetic progestin is added. Natural estrogen with a combination of estradiol and estriol with natural progesterone is a much better choice.

Why aren’t the superior natural hormones promoted more?
They are very popular in Europe and are becoming more popular as more American women learn about the advantages. Because no patent protection can be granted for these natural hormones in the US, no drug company can expect large profits from the sale. Thus, with little financial incentive, no major drug company produces or promotes them.