The so-called bio-identical hormones have the same molecular structure as those produced by female bodies, while “classic” hormones differ chemically. The estrogen Classics generally prescribed in North America are made from the urine of pregnant mares: they are called “conjugated equine estrogens,” or ECEs. They are sold in the market under the Premarin® brand. Bioidentical estrogen is a molecule ofestradiol-17β, the main estrogen produced by the female body.

As to progestins most prescribed in classic hormone therapy (Provera®), they are made from a derivative of progesterone which has been chemically modified to make it assimilable by the body; it is medroxy-progesterone acetate (MPA). Doctors who use bioidentical therapy instead prescribe progesterone micronized. The micronization technique transforms progesterone into tiny particles that are well absorbed by the body.

All hormones, bioidentical or not, are made or modified in the laboratory. So these are not natural health products.

The D^re Sylvie Demers prescribes bioidentical hormones. According to her, it is the best choice because “these hormones have the same beneficial effect as the hormones naturally made by the body before menopause”. According to its analysis of scientific data, this treatment has the same advantages asclassic hormone therapy (relief of symptoms of menopause and prevention of several diseases), but without the risks.

According to the D^re Michèle Moreau, classic hormone replacement therapy has long been shown to be effective in relieving symptoms of menopause : hot flashes, fatigue and sleep problems, vaginal dryness and urogenital atrophy, mood problems, loss of skin tone and joint pain. When taken early – as early as menopause or shortly before – estrogens are also effective for prevention of diseases related to aging : osteoporosis, colon cancer, cardiovascular disease and possibly Alzheimer’s disease.

“Having said that,” she says, “do not think that thehormone therapy is a fountain of youth! Our skin ages anyway and so does the rest! This is a great helper that is on top of everything well known for healthy aging. And don’t forget that many women will be fine without hormone therapy. “

Estrogens: oral or cutaneous?

According to the D^re Sylvie Demers, the classic combination ofconjugated equine estrogens (ECE) say meat progestins AMP (Provera®) can have harmful consequences for your health. Regarding conventional estrogens administered by oral, they slightly increase the risk of thrombo-embolie and tend to increase the level of C reactive protein and triglycerides in the blood, which are risk factors for cardiovascular disease.

L’bioidentical estrogen through the skin (patch and estradiol-17β gel) does not present this problem, according to D^re Demers. On the contrary, it has anti-inflammatory properties and improves the lipid balance. “It also has beneficial properties for the brain: increasing blood circulation, stimulating the growth of neurons and increasing the number of nerve connections, for example,” she says.

According to the D^re Michèle Moreau, for the vast majority of women, bioidentical estrogens do not offer any real advantages over conjugated equine estrogens. “There is no doubt thatestradiol-17ß transdermally offers a very physiological way of delivering estrogen, which most closely resembles the functioning of the ovaries before menopause. But its long-term effects, positive or negative, have not been well studied. “

The D^re Sylvie Dodin also believes, like the D^re Moreau, to the full effectiveness of conjugated equine estrogens. But, for women in excess weight or at risk of cardiovascular illnesses, she thinks the dermal route is safer. “But it is the transmission route that is important, and not the fact that it is bioidentical,” she stresses.

Note that doctors do not recommend the prescription of hormones to prevent only aging-related diseases. A healthy lifestyle – no smoking, good nutrition, a healthy weight, physical activity – is much more effective than hormones in ensuring long-term health.

Progestins and progesterone

As to progestins, their only role in conventional hormonal therapy is to prevent the endometrial cancer (estrogen stimulates the proliferation of cells in the uterus). Prescribing hormones must necessarily include both, except in women whose uterus has been surgically removed.

The D^re Sylvie Demers finds the AMP-type progestogen (Provera®) worrying: it seems to increase the risk of breast cancer and would be harmful for the heart and the nervous system. According to her, the bioidentical progesterone does not have an aggravating effect on these diseases and even exerts a protective effect.

As for the breast, it should be remembered that, in the Women Health Initiative (WHI) study – see the box above on this subject – the increase in cases of this cancer was observed in women who were taking breast cancer. estrogen and progestins (AMP), and not in those taking only conjugated equine estrogens.

“But, argues the D^re Sylvie Dodin, scientifically, we cannot extrapolate and say that progestins have caused an increase in cases of breast cancer. We cannot, either, deduce that the so-called bioidentical progesterone would not present the same risk. Having said that, I still prefer bioidentical progesterone because it may be less risky than progestins and, more importantly, because it relieves sleep problems, which progestins do not. “

According to the D^re Michèle Moreau, we have to look more generally. Yes, there was a very slight increase in breast cancer in the women in the WHI study who took theclassic hormone therapy – and this has been widely publicized – but at the same time, there has been a reduction in colon cancer. In fact, the total number of cancers remained the same in the group receiving hormone therapy as that in the group without hormone therapy.

“The risk of breast cancer associated with hormone therapy remains possible, although qualified as” rare “according to the categories of the World Health Organization, she says. Over 85 large studies have looked at this with conflicting results. I have never seen such a complex and controversial subject in medicine! “

What the medical authorities think

In its last update from January 2009, the Society of Obstetricians and Gynecologists of Canada (SOGC) lists all hormonal treatments available, including bio-identical products⁵. However, the SOGC does not make any recommendations in favor of one type of product or another.

In France, the French Agency for the Safety of Health Products (AFSSAPS) also does not make a firm recommendation in favor ofbioidentical hormone therapy. In its 2008 update on hormone treatment for menopause, however, the Agency mentions that the level of risk of breast cancer “May depend on the nature of the progestogen associated with estrogen and would in particular be lower with micronized progesterone or dydrogesterone”. But the organization considers that the data is not yet strong enough to modify the recommendations issued in 2006⁶.

The D^re Sylvie Demers favors the measurement of hormone levels by blood. The level of free hormones in saliva does not adequately reflect the level of hormones present in the tissues, she points out.

For her part, gynecologist Sylvie Dodin believes that the only way to dose hormones is by trial and error. “The best indicator is the effects: if a woman has no more hot flashes, but her breasts are very painful, it is because the dose is too strong. Anyway, in premenopause, the fluctuations are so great that an ideal dosage cannot be determined by a blood or saliva test. I still follow up closely with women at risk, such as smokers. “

For the D^re Michèle Moreau, no analysis is necessary because the dosages ofhormone therapy having a beneficial effect in the short and long term have been well established. No studies have shown that increasing the dose increases the risk of breast cancer, or vice versa, she says.

The opinion of the D^re Dodin

In her practice, Sylvie Dodin mainly prescribes bioidentical hormones (pharmaceutical brand) because estrogen (estradiol-17β) is supplied by dermal and because progesterone has a beneficial effect on the sleep. And that’s what she herself will choose at the appropriate time. She recommends that women stop after five years, as a precaution, but agrees to prescribe it longer if they wish.

“We can never prove that bioidentical estrogen and progesterone are more effective or less dangerous. The scale of research that this would require is inconceivable. But thanks to the WHI study, we can more precisely measure the risks and benefits of hormones, and women know what they are exposing themselves to, ”she says.

The opinion of the D^re step

Sylvie Demers does not believe that it is necessary to stop thebioidentical hormone therapy after some years. “Why stop safe treatment that improves quality of life and has beneficial preventive effects? “According to her, the risk is especially not to take hormones at the menopause: increased risk of atherosclerosis, osteoporosis, high blood pressure and dementia. “Not to mention all the other beneficial functions of estradiol-17β and progesterone. I am convinced that the drastic fall of these sex hormones is an important factor in the process of aging She adds.

The opinion of the D^re Moreau

For Michèle Moreau, everything depends on the goal. Four or five years of treatment is usually sufficient to relieve acute symptoms. But to prevent osteoporotic fractures in old age, it should be taken for 20 years, and the prevention of heart disease requires lifelong use. For maximum benefit, hormone therapy should also be started at the start of the treatment. menopause and no, as in the WHI study, 15 to 20 years after the onset of menopause.