As doctors say HRT scare stories are putting women's health at risk, a writer who has studied the controversy for years helps you separate the fact from the fiction
On July 9, 2002, American health officials changed the course of thinking about women's health for ever.
At a packed press conference in Washington, they announced with complete confidence that Hormone Replacement Therapy (HRT) used by millions around the globe to cope with debilitating menopausal symptoms such as hot flushes, night sweats, reduced libido and weakened bones, was not safe.
An acrimonious debate erupted among the global scientific community. Meanwhile, women panicked and sales of HRT plummeted.
In the UK alone, the number of women using HRT halved from two million in 2002 to one million in 2005. Only yesterday it was revealed that the number of prescriptions for HRT has fallen by almost half in the past six years.
The source of all this panic was the Women's Health Initiative (WHI), a major American government-sponsored study of more than 27,000 women.
It had set out to determine whether HRT helped prevent heart disease, a benefit widely ascribed to its use.
As it turned out, in the first group of 17,000 women to be tracked, HRT hadn't helped.
In fact, women in this study who used the drug had more heart attacks and breast cancer than non-HRT users.
They also had fewer hip fractures and lower risk of colon cancer, but that potential good news was eclipsed by the heart and breast worries.
So American health officials decided the risks to the women in the study outweighed the benefits, prompting them to take the highly unusual step of stopping the main part of the hormone study early and alerting the world to their findings in the most dramatic fashion possible.
Dr Jacques Rossouw, acting director of the WHI at the time, explained that the press conference was arranged with the specific goal of creating "high impact".
The goal, he says, was to shake up the medical establishment and change the thinking about HRT.