Women can safely use hormone therapy in the short-term early in menopause to alleviate symptoms such as hot flushes, a panel of Canadian experts in women's health said Thursday in releasing new guidelines.

The Society of Obstetricians and Gynaecologists of Canada commissioned an updated review of research on menopause and osteoporosis that appears in this month's issue of the group's journal.

Some menopausal women were needlessly scared away from hormone therapy (HT) in 2002, when the Women's Health Initiative, a large clinical trial in the U.S., concluded that the drugs increased the risk of heart disease, stroke and breast cancer, compared with a placebo, the group said.

Breast cancer risk in context

"Unfortunately, the WHI study created fear that the short-term use of HT for menopausal symptoms will increase your chances of getting breast cancer," said Dr. Robert Reid, a professor of obstetrics and gynecology at Queen's University in Kingston, Ont., and the lead author of the update.

"We now see that concern about that risk is unfounded and is the result of a distorted perspective about the influence of HT on breast cancer."

The average age of women in the 2002 study was 62 — older than when most women begin HT.

Using HT for more than five years has little appreciable effect, 1.3 times or 0.08 per cent, on breast cancer risk, Reid noted.

In comparison, factors such as first pregnancy after age 35, post-menopausal obesity or alcohol use increase the risk of breast cancer by 1.7 to 1.9 times, 1.2 times and 1.2 times respectively.

Personal risk-benefit checks

Women need to discuss their personal cases with their doctors, since different forms of HT, such as a transdermal patch, may be more appropriate, Reid added.

Dr. Jacques Rossouw, project officer for the Women's Health Initiative, said he agreed that the study's data indicated that the risks of short-term use of HT in women immediately after menopause are low.

But Roussouw added that he felt the Canadian society downplayed the small risk of breast cancer and stroke.

"Look at your risk factors and consider whether you want to trade relief of symptoms for the real risk of … stroke, blood clots and breast cancer," advised Roussouw, a researcher in cardiovascular disease prevention at the U.S. National Heart, Lung and Blood Institute, in Bethesda, Md. "It's a real risk."

Benefits for bone loss, heart health

The update is the group's first review since 2006 on menopause, and is meant to put the WHI results in context. It also includes new information on osteoporosis risk and the effects menopause can have on cardiovascular disease and cognitive function.

For example, one in two women over 50 will suffer an osteoporosis-related fracture that causes chronic pain, reduced ability, loss of independence and increased risk of death, said Dr. Aliya Khan, a professor in the division of endocrinology and geriatrics at Hamilton's McMaster University, and a co-author of the review.

Hormone therapy is highly effective for preventing bone loss and osteoporosis-related fractures, the panel said.

"It is clear that the window for prevention needs to open at a much earlier age to ensure that women are not sidelined in midlife by this devastating disease," Khan said.

Hormone therapy also does not increase the risk of cardiovascular disease in newly menopausal women when started within the first 10 years of menopause, the group concluded.

The review comes as the largest demographic from the "baby boomer" generation turns 50 and may seek relief from menopausal symptoms. In Canada, there are now 2.5 million women aged between 45 and 54.

Hormone therapy is a combination of estrogen and progestin or estrogen alone. It is used to relieve moderate to severe menopausal symptoms such as hot flashes, night sweats, vaginal dryness and mood changes as hormone levels wane.

Official guidelines recommend women take hormone therapy for menopausal symptoms for the shortest time possible and at the lowest dose.

Many of the authors have advised pharmaceutical companies, but no drug companies were involved in the review.

With files from Canadian Press