Why is hormone replacement therapy so controversial?

Source: Best Health Magazine, September 2012; Image credit: iStockphoto.com

‘What do you think about bio­identical hormones?’ asked a woman in her 50s who had come as a ‘walk-in’ to the clinic where I practise. ‘The gynecologist my family doctor referred me to told me that they’re unproven and it’s better to go with traditional hormone replacement. I’m scared to do that, though.’

During my medical training I had learned the basics of women’s hormonal health. I knew how to ask about or listen for symptoms of menopause, confirm the ‘diagnosis,’ and administer standard doses of synthetic hormone replacement therapy (HRT). Then, in 2002, after I had been practising for two years, came the results of the Women’s Health Initiative (WHI). This large study examining synthetic estrogen and progestin commonly used in HRT was suspended when subjects experienced an increased risk of breast cancer, cardiac events, strokes and blood clots. Deeply shaken, I hesitated to start any woman on synthetic HRT, other than to relieve the most debilitating hot flashes. I echoed the new position of leading experts in the field, cautioning women to limit use of HRT to no more than five years at most.

The reasoning behind HRT in general is straightforward. At any time from our early 30s into our late 40s, women enter perimenopause. During this time, progesterone levels drop and estrogen levels dominate. Since progesterone helps us sleep and keeps us calm, the imbalance creates symptoms such as sleeplessness and anxiety.

Later, as we enter menopause, our ovaries stop producing estrogen and we face low levels of both crucial hormones. Estrogen alone has more than 400 functions: Among other things, it regulates body temperature, maintains memory, boosts our mood and keeps our skin young. If it’s missing, we experience hot flashes, memory lapses and ‘brain fog,’ moodiness and more rapidly aging skin.

HRT aims to replace these dwindling hormones, thereby relieving symptoms and protecting our general health. Synthetic HRT consists of estrogens made partially from the urine of pregnant horses, and progestins, which are quite different structurally from our own progesterone. Bioidentical HRT consists of hormones extracted from plant sources such as yams and soy; they are structurally identical to our own hormones. Proponents of bio­identical HRT state that the problem with synthetic hormones is that they are too different from our own; they stimulate additional ‘unnecessary’ hormone receptors and fail to replace some of the critical functions of our natural hormones, creating potentially serious side effects.

When I first heard about bioidentical HRT, it sounded great, but I worried it hadn’t been rigorously evaluated. Leaders in women’s health, such as the Society of Obstetricians and Gynecologists of Canada, maintain a similarly skeptical position. Yet some of the best physicians I know have started practices that focus on bioidenticals and women’s midlife health.

A study published in 2009 in Postgraduate Medicine reviewed the available evidence and concluded that bioidentical hormones are associated with lower risks and are more efficacious than their synthetic and animal-derived counterparts.

So why the controversy?

After the frightening results of the WHI, it’s understandable that leading groups in the field want more proof from studies on large groups of women before endorsing this new era in hormones. They also say urine and saliva testing done by many bioidentical practitioners’to determine a woman’s level of hormones, among other things’isn’t accurate. Yet many practitioners swear by them, saying their patients get excellent results and fewer side effects from bioidenticals than from synthetic HRT.

There is one thing both sides agree on. The amount of distress you’ll experience in perimenopause or menopause is hugely tied to your general health. Stress hormones mess with our other hormones, and stressed-out women, as well as those with unhealthy eating habits, have a harder time with hormonal transitions.

So, as we wait for more research to give the final word on this topic, remember to take care of yourself’you can never go wrong with that.

Dr. Susan Biali is a practising GP, wellness expert and life coach. She is the author of Live a Life Your Love: 7 Steps to a Healthier, Happier, More Passionate You. She is also a regular contributor to Best Health. You can follow her on Twitter @DrSusanBiali.

This article was originally titled "Weighing in on HRT" in the September 2012 issue of Best Health. Subscribe today to get the full Best Health experience’and never miss an issue!