Progesterone or Progestins
Knowing The Difference Can Save Your Life

The recent publication of the Women's Health Initiative study on hormone replacement therapy for menopausal women has caused great concern in the general public as well as with many health care professionals. While some of these concerns are justified, others are not. This brief document is designed to educate you regarding the major findings of this study and about some of the available alternatives.

The purpose of the Women's Health Initiative study was to define the risks and benefits of strategies that could potentially reduce the incidence of heart disease, breast and colorectal cancer, and fractures in postmenopausal women. The researchers concluded that the women randomized to Prempro therapy (conjugated equine estrogen plus medroxyprogesterone acetate) developed an increased risk of breast cancer after receiving the medication for five years. This increased risk was reported as 26% (relative risk) or 1 new case of breast cancer for every 100 women being treated for 5 years (absolute risk). This finding was not a surprise to those of us who have been recommending human bioidentical a.k.a. “natural” hormone therapy, as there have been several previous studies with synthetic hormones that have reached the same conclusion.

It is important to note that the increased risk of breast cancer seen in this study has been linked to the medroxyprogesterone component of the Prempro , as the women taking Premarin (conjugated equine estrogen alone) did not experience an increased incidence of breast cancer at the five year mark. In fact, one aspect of this study is continuing to evaluate the risks and benefits of Premarin therapy.

Unfortunately, many health care professionals have erroneously concluded that any hormone therapy will result in an increased risk of breast cancer and have informed their patients to discontinue their hormones. This strategy is an over reaction to the information learned in this study and clearly will not work for every woman. While some women will do just fine without hormone therapy, many others, especially women who have had a hysterectomy, benefit greatly from hormone replacement therapy. So before jumping to the conclusion that all hormones are bad, we need to educate ourselves about the specific effects and side effects of the various hormones. In particular, the difference between synthetic progestins (medroxyprogesterone and norethindrone) which have been shown to increase the risk of breast cancer and the human bioidentical hormone, progesterone, which has been shown to be protective against breast cancer. With such similar sounding names it is easy to see why many people confuse progesterone with the synthetic progestins, thinking that they are one in the same.

So why is everyone so confused? Years ago the pharmaceutical companies created a class of drugs called progestins to mimic the uterine protective activity of the body's own hormone, progesterone. Following the development of the progestins, the medical literature began using the words progestin and progesterone interchangeably, as synthetic progestins were the only commercially available medications that could be prescribed. This practice continues to this day even though they are two distinctly different hormones as we will explain below.

What are Progestins?

When Premarin (conjugated equine estrogen) was first introduced in the United States, it was prescribed alone to women even if they still had a uterus. After many years of this practice, an increase in uterine cancer was associated with the use of the Premarin . The pharmaceutical companies needed to develop a medication to protect women from getting uterine cancer when they were taking estrogen (Premarin ) alone. They knew that progesterone was how the body protected itself against too much estrogen, so they developed a class of drugs called progestins to mimic this uterine protective activity. The pharmaceutical companies used the basic chemical structure of progesterone but changed it in order to make the progestins and patent them.

The problem with changing a hormone's structure is that a hormone must be identical in structure to our body's own hormones to operate in the same way. Any change to the chemical structure will alter the way that hormone acts in our body. See the structure of progesterone and medroxyprogesterone acetate (a progestin) below. While these synthetic progestins look similar to natural progesterone, they do not produce the same effects everywhere in our body.

Which Hormones are Synthetic Progestins

The brand names of medications that contain synthetic progestins include:
• Provera , Amen , Cycrin , Prempro , Premphase each contain medroxyprogesterone acetate.
• Aygestin, Norlutate, Femhrt, Combipatch each contain norethindrone acetate.
• Ortho-Prefest contains norgestimate.

There are studies that have concluded that medroxyprogesterone and norethindrone actually act like an anti-progesterone and cause a progesterone deficiency in the body11. It is this anti-progesterone activity that increases the risk of breast cancer for those women taking progestins.

Why You Need Human Bioidentical Progesterone!

Progesterone is a hormone that is naturally produced by the female ovaries at ovulation. Ovulation occurs less frequently as women age, and stops completely at menopause. The progesterone that we use to make natural hormone medications is identical in its chemical structure to the body's own progesterone. While it is derived from wild yams and soybeans, it is a pharmaceutical hormone not an herbal medication. We cannot just eat wild yams or soybeans and get the same benefits because our bodies do not have the proper enzymes to convert the wild yam or soybeans to progesterone.

All women, even those who have had hysterectomies, should use progesterone as part of their hormone replacement therapy. Unlike the synthetic progestins, progesterone has many beneficial effects in the human body besides protecting against uterine cancer such as:
• Helps protect the breast, and probably the ovaries from cancer.
• Acts as a natural diuretic.
• Produces a calming, anti-anxiety effect.
• Decreases PMS and menstrual flow.
• Enhances your body's immune system defenses.
• Improves the breakdown of fat into energy.
• Decreases craving for carbohydrates and sweets.
• Softens fibrocystic breasts and reduces tenderness and pain.
• Contributes to the formation of new bone tissue.
• Increases HDL, the body's good cholesterol.
• Essential for maintaining pregnancy.
• Promotes normal sleep patterns.
• Improves thyroid hormone activity
• Helps improve sex drive.

Progesterone is available from compounding pharmacies as creams, capsules, troches, lotions, drops or suppositories. Only one pharmaceutical company manufactures natural progesterone as an oral capsule under the brand name Prometrium . It is in a peanut oil filled capsule and should be avoided by those with peanut allergies. If your hormone therapy is a tablet, or a patch it is a synthetic progestin, not progesterone.

Show Me the Proof! (Studies on Natural Progesterone)

Many healthcare practitioners are unaware that there are many studies on progesterone. However, there is an ever-increasing body of literature documenting the beneficial and protective effects of progesterone. These are listed below.

I. Progesterone protects and helps build your bones.

1. There is evidence that bone forming cells are influenced by progesterone and contribute to bone formation. 2,.3,4,5, 6 Progesterone acts through regulation of osteoblasts and by binding to glucocorticoid receptors to prevent bone loss.

II. Progesterone helps protect breast tissue.

1. There have been many studies indicating the protective effects progesterone has on breast tissue. Progesterones' protective affect is through induction of estrogen dependent cancer cell death (apoptosis) by upregulating the P53 gene. This means that progesterone has strong antiproliferative (anti-growth) effects on breast cancer cells. Progesterone acts like an anti-estrogen.

2. The synthetic progestins, like norethindrone and medroxyprogesterone acetate in Prempro , Provera , etc occupy the progesterone receptor and prevent stimulation of the P53 gene. This induces a progesterone deficiency and may increase the risk of breast cancer because there is no opposing action.

3. A deficiency of natural progesterone also allows breast cancer cells to grow unopposed.

In fact a progesterone deficiency was shown to increase the death from all cancers by 10 fold and increase the incidence of premenopausal breast cancer by 5.4 fold as documented by a 1981 study at John Hopkins.

4. There have been many studies indicating an increase risk of breast cancer in women using synthetic progestins for many years. The last study this summer was no surprise to those of us following the literature.

III. Progesterone helps protect brain function.

1. Progesterone is critical to ensuring normal brain development and provides neuroprotection.

2. Progesterone promotes myelin repair in the brain and is being studied for the treatment of brain injuries and multiple sclerosis.

3. Progesterone also affects the ways the brain functions and sends signals to the body. It is being studied for treatment of neurodegenerative disorders such as Alzheimer's disease.

IV. Progesterone helps protect the heart.

1. Progesterone exerts no negative effects on lipid levels (cholesterol) and vascular tone (blood vessel pliability) where as the synthetic progestins have been shown to have negative effects on the heart.

2. Progesterone also prevents the growth and movement of the cells that are involved in the formation of plaque that blocks arteries in the heart and brain.

3. Progesterone also protects the vascular system by helping to relax the muscles in the blood vessels via the enhancement of nitric oxide.

V. Progesterone protects the uterus.

1. Both oral and topical progesterone will protect against uterine hyperplasia. There are many studies proving the protective effects of oral progesterone and a recent study also provides evidence that topical progesterone cream will offer the same protection against estrogen stimulated growth.

Conclusion:

As you can see, the scientific literature shows that bioidentical progesterone exerts many beneficial effects throughout the body. Its safety has also been well established through decades of use in the treatment of fertility problems and as well as premenstrual syndrome. This remarkable hormone offers many benefits for those of us who use appropriate amounts to oppose the detrimental effects of excess estrogen. Synthetic progestins cannot be substituted to achieve the favorable actions of bioidentical progesterone. Don't let anyone confuse you; bioidentical progesterone is beneficial for your continued good health!

Please contact us if you would like more information about progesterone or any other hormone used in bioidentical hormone therapy.

List of literature citations is available on our website under Natural Hormone Therapy

Disclaimer

The viewpoints expressed in this newsletter are based upon scientific research, and the personal and professional experience of the authors. They are not intended as a substitute for consulting with your physician or other health care provider. You should consult with your healthcare practitioner prior to starting any vitamin, herbal or other therapies.

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