Synthetic non-human hormones are less safe and offer fewer health benefits, compared to hormones that are identical to what the body produces naturally
In 2002 & 2004 the results of the Women's Health Initiative (WHI) study were published showing that the combination of an oestrogen and progestin for the treatment of menopausal symptoms increased the risk of breast cancer, heart disease and blood clots by up to 50% 1,2 . This prompted a scurry for research to determine why this was, and for safer alternatives. The reasons why are only beginning to surface now.
Firstly, the dosage used was too high. As a result of the WHI study, current recommended doses have dropped to three times lower than the doses used prior to 2002.
Secondly, the hormones were administered orally, as opposed to being applied to the skin. In the Lancet3 medical journal in 2003, and again in 2005 & 2007, in the medical journal, Circulation 4,5, the results from the Estrogen and Thrombo-embolism Risk Study were published. These results showed that orally administered oestrogens cause the liver to produce huge amounts of blood clotting factors, increasing the risk of heart attacks and stroke. This didn't occur when hormones were applied to the skin because topically applied hormones are absorbed directly into the bloodstream, bypassing the liver.
Finally, the types of hormones used were too potent and were not identical to the hormones that the body produces naturally. Hormones identical to those that occur naturally in the body are called bio-identical hormones. These include progesterone, oestradiol, oestriol and oestrone. The types of hormones used in the trials were conjugated oestrogens, extracted from horse urine. These contain a type of oestrogen not found in humans, called equilin. A second type of hormone used in the studies was a non-bio-identical progestin called medroxy-progesterone acetate. Bio-identical progesterone was not used. Research published in the Journal of Steroid Biochemistry6 in December 2005, in an article entitled ‘Pregnancy, progesterone and progestins in relation to breast cancer risk', reported that whereas non-bio-identical progestins increased the risk of breast cancer, bio-identical progesterone conversely reduced breast cancer risk.
Therefore, a safer alternative to conventional oral HRT is to use transdermally applied bio-identical progesterone. This should be applied to the skin in a liposomal gel, usually applied to the inside areas of the arms, twice a day. In a liposomal gel the hormone is encapsulated into tiny liposomal beadlets made from lecithin, and carried through the skin into the bloodstream, bypassing the liver. The October 2005 issue of the Journal of the American Association of Pharmaceutical Scientists7 reported that liposomal gels ensure effective delivery of medicines through the skin and into the bloodstream, unlike conventional creams and gels that mostly absorb into the outer layers of skin only.
Oestrogen and progesterone work in balance with each other. When the balance is upset then irregular menstruation and other problems can manifest. These occur when the balance is shifted in favour of ‘oestrogen dominance', which also increases the risk of cancer. Oestrogen dominance typically occurs at the time around menopause (this time is known as perimenopause). If you are already on oestrogen HRT, then adding bio-identical progesterone to your therapy helps reduce the increased risk of oestrogen dominance-induced breast cancer (reported in the 1995 issue of Journal of Fertility and Sterility) 8. Therefore, bio-identical progesterone can be used alone, or in combination with conventional oestrogen HRT. If you are on conventional HRT and want to make the change to bio-identical progesterone, then it is advisable to do so under your doctor's supervision.
Reasons for using bio-identical progesterone liposomal gels include premenstrual syndrome, menstrual irregularity, menopausal symptoms (such as hot flushes and night sweats), endometriosis, benign ovarian cysts, fibroids and hormone replacement therapy. Although there is some evidence showing that progesterone may also be useful for increasing bone density, more research is needed in this area.
Besides not forming blood clots, there are other advantages to using a liposomal gel rather than a tablet. Many medicines are administered through the skin (such as oestrogen, nicotine and nitroglycerin heart medication). Progesterone is also absorbed through the skin, into the bloodstream. Any medicines taken orally are absorbed into a part of the bloodstream that first goes directly to the liver, before it is delivered elsewhere in the body.
Up to 80% of orally delivered hormones are destroyed by the liver, before even reaching the rest of the body.
This means that we must use much larger doses when using tablets as opposed to liposomal gels, putting huge strain on the liver. Absorbing it through the skin into the general circulation (as opposed to first going to the liver), is much more like the way the ovaries naturally secrete progesterone, and requires lower doses to be effective.
BIO-IDENTICAL PROGESTERONE VERSUS SYNTHETIC PROGESTINS
Bioidentical progesterone is exactly like the progesterone produced by your ovaries. Synthetic progestins are made to be similar, but not identical, to the body's progesterone, with many actions similar as well. However, women have many more side-effects on synthetic progestins. These include weight gain, water retention, headaches, acne, mood swings and depression. Synthetic progestins are also not friendly to the heart's coronary arteries, and they negatively impact on cholesterol balance. Although synthetic progestins have many disadvantages, they also have some advantages over bio-identical progesterone. They are readily available in all pharmacies, they are very inexpensive, they only need to be taken once a day, and they are more effective at stopping heavy dangerous bleeding.
However, the most convincing reason to use bio-identical progesterone is that it is what the body makes naturally. Surely the hundreds of thousands of years of natural evolution of this hormone in our bodies make it the hormone of choice, especially when using it over a long period of time. I feel it is the safest alternative to conventional HRT, with fewer side-effects and more benefits.
(Bio-Identical progesterone is made by Solal Technologies)
References
1. J. E. Rossouw et al "Risks and benefits of estrogen plus progestin in healthy postmenopausal women: principal results From the Women's Health Initiative randomized controlled trial" in Journal of the American Medical Association (2002) Volume 288, pages 321-333.
2. G. L. Anderson et al "Effects of conjugated equine estrogen in postmenopausal women with hysterectomy: the Women's Health Initiative randomized controlled trial" in Journal of the American Medical Association (2004) Volume 291, pages 1701-1712.
3. Scarabin PY, Oger E, Plu-Bureau G; "EStrogen and ThromboEmbolism Risk Study Group. Differential association of oral and transdermal oestrogen-replacement therapy with venous thromboembolism risk."; Lancet. 2003 Aug 9;362(9382):428-32
4. C. Straczec, et al "Prothrombotic mutations, hormone therapy, and venous thromboembolism among postmenopausal women: impact of the route of estrogen administration" in Circulation (2005) Volume 112, pages 3495-500).
5. Marianne Canonico et al., "Hormone Therapy and Venous Thromboembolism Among Postmenopausal Women -Impact of the Route of Estrogen Administration and Progestogens: The ESTHER Study"; Circulation Feb 2007;115;840-845 ).
6. Campagnoli C.; "Pregnancy, progesterone and progestins in relation to breast cancer risk"; J Steroid Biochem Mol Biol. 2005 Dec;97(5):441-50).
7. Kumar R, Katare OP.; Lecithin organogels as a potential phospholipid-structured system for topical drug delivery: a review; AAPS PharmSciTech. 2005 Oct 6;6(2):E298-310
8. Chang KJ, Lee TTY , Linares-Cruz G, Fournier S, de Lignieres B. Influences of percutaneous administration of estradiol on human breast epithelial cell cycle in vivo. Fertility and Sterility 1995; 63; 7865-7891.
BRENT MURPHY, B.PHARM (RHODES), MPS, IS DIRECTOR OF PROFESSIONAL AFFAIRS (RESEARCH, DEVELOPMENT & TRAINING) FOR SOLAL TECHNOLOGIES. HE IS ALSO AN EXECUTIVE BOARD MEMBERS OF THE HPA