Hormone Replacement
Bioidentical (Natural) vs Synthetic Hormones
Bioidentical hormones are sometimes referred to as natural hormones. Natural hormones are found in nature from wild yam and soy. Bioidentical hormones are created in a compound pharmacy also from wild yam and soy. The difference is bioidenticals are compounded to be identical to what our ovaries naturally produce. Bioidentical hormones have the same molecular structure as the hormones your own body creates.
Natural hormones bought over the counter or on the internet are frequently not micronized or found in high enough dosages to be effective. Micronized means it is broken down in particles that can be absorbed through the skin. You could bathe in the hormones provided over the counter and your skin would still not absorb the needed amount of hormones.
Synthetic hormones are hormones manufactured and patented by pharmaceutical companies. These essentially are estrogen, progestins,and testosterone. Synthetic hormones have added side chains like methyl and acetate groups that are attached to the original molecule to create synthetic hormones.
Why?
Because pharmaceutical companies can not patent anything that is bioidentical or natural (existing in nature) However, with that being said, there are several pharmaceutical companies now marketing bioidentical hormones. That may sound conflicting, let me explain. The pharmaceutical companies recognize that women want alternatives for hormone replacement therapy. The pharmaceutical companies have developed unique delivery systems like the patch and a new form of gel or capsule that has previously not been developed and they patent the actual delivery system ie the patch is actually patented not the hormone.
Why don't all physicians prescribe bioidentical hormones?
Much of what we are taught as physicians about drugs comes from pharmaceutical companies who have done tremendous research and marketing costing millions of dollars. In the past before pharmaceutical companies started manufacturing bioidentical hormones, they had very little interest in having physicians prescribe medications in which they had no financial gain.
What's my take?
I think it's great for several reasons. First many insurance companies don't cover compounded formulations because they are not FDA approved. If a pharmaceutical company develops and markets a form of hormone replacement therapy even though it's still bioidentical, it will be covered by insurance. It may sound absurd, but that's the insurance game. The fact that they are coming out with bioidentical alternatives means we're on the right track, just ahead of the game. Secondly, other physicians who are not trained to use bioidenticals will feel more confident offering the standardized prescriptions.
Women will still need individualized treatment and monitoring to make sure that their hormone levels are adequate to protect the bone and the uterus. This is done with serum testing at intervals appropriate for the individual hormones the patient is prescribed.
Are bioidenticals safer?
The problem with claiming they are safer from a scientific standpoint is hard to do. Pharmaceutical companies have not conducted the necessary clinical trials that would establish safety because they haven't been able to make money - no patent and no money. They have not had the incentive to spend hundreds of thousands or even millions of dollars to market a drug they can't sell. This will all change now that they have several bioidentical hormones in the pipeline. I suspect we will see more and more studies performed over the next few years.
Theoretically, it makes sense that they are safer because they are identical to what your ovary produced before menopause. The body doesn't see these hormones as foreign and doesn't mount an immune response to the added chemicals. Bioidentical hormones are easier for your body to metabolize and are free of some unpleasant side effects associated with synthetic hormones.
There are several European medical studies that advocate the safety of bioidentical hormones over synthetic hormones. Keep in mind that synthetic hormones have been used for the last 50 years without any long term studies. The Women's Health Initiative in 2002 was the first randomized placebo controlled trial that addressed the safety of synthetic hormones.(link to WHI study)It found that the risks outweigh the benefits of combination (Prempro) hormone replacement therapy. Nonetheless most physicians are still prescribing these hormones regardless of the long term studies.
