International experts have called for a return to a "rational use" of hormone therapy (HT), initiated near the menopause, 10 years after a report caused a dramatic drop in HT.
The findings have been published in a series of articles in the International Menopause Society's Climateric, and puts into perspective the findings of a July 2002 publication of the first Women's Health Initiative (WHI) report, which said it increased the risk of breast cancer, heart disease and strokes, scaring many women off HT.
The scientists, some who worked on the original WHI study, said evidence over the last decade has changed and supports a return to a "rational use of HT, initiated near the menopause".
The initial press release following the 2002 report over-emphasised a relatively small increase in breast cancer, the scientists said, distorting the overall view of the report
Summarising the recent findings, authors Robert Langer, JoAnn Manson, and Matthew Allison concluded "classical use of HT" - MHT initiated near the menopause - will benefit most women who have indications including significant menopausal symptoms or osteoporosis.
"With 10 years hindsight we can put the lessons learned from the WHI HT trials into perspective," Dr Langer, principal scientist at the Jackson Hole Center for Preventive Medicine, Jackson, Wyoming, said.
"In some ways we've come full circle - studies in recently menopausal women that suggested protection against major diseases led to testing whether that would carry over to older women who have even greater risks of heart attacks and fractures. That hope proved false.
"Unfortunately the results were wrongly generalized back to women like those who inspired the study. Information that has emerged over the last decade, shows that for most women starting treatment near the menopause, the benefits outweigh the risks, not just for relief of hot flashes, night sweats and vaginal dryness, but also for reducing the risks of heart disease and fractures.
"Overgeneralising the results from the women who were - on average - 12 years past menopause to all postmenopausal women has led to needless suffering and lost opportunities for many. Sadly, one of the lessons from the WHI is that starting HT 10 years or more after menopause may not be a good idea, so the women who were scared away by the WHI over this past decade may have lost the opportunity to obtain the potential benefits."
Professor Manson, from the Harvard Medical School and Brigham and Women's Hospital, Boston, said the original WHI report did clarify that for older women at high risk of cardiovascular disease, the risks of HT far outweighed the benefits.
"This halted the increasingly common clinical practice of prescribing HT to women who were far from the onset of menopause. Unfortunately, these findings were extrapolated to newly menopausal and healthy women who actually had a favourable benefit: risk ratio with HT. The WHI results point the way towards treating each woman as an individual," Professor Manson said.
"There is no doubt that HT is not appropriate for every woman, but it may be appropriate for many women, and each individual woman needs to talk this over with her clinician."
WHI researcher Professor Matthew Allison from the University of California said it was important to put the results from the 2002 trials into context.
"That is, being obese, not exercising or excess alcohol consumption confer higher absolute risks for breast cancer than HT use."