The Australian National University reported a seven percent reduction in the incidence of breast cancer among women over 50 in the three years to 2003.
Researcher Emily Banks said there had been a 40-per-cent fall in the number using HRT and the results of the study showed the merits of women questioning whether they should use the treatment.
"It's probably a good reminder and it's timely for them to really look at whether they need to be using HRT, whether their menopausal symptoms are severe, and whether they actually weigh up the risks and benefits," Banks said.
"We've reduced breast cancer by quite a lot, but there's still more that can be done."
Banks said the decrease could not be explained by other factors because there had been no drop in the incidence of breast cancer among younger women, who rarely take HRT.
"That really large drop in HRT use from 2001 to 2003 really seems to be the only big risk factor that we can see that change dramatically at that time," she said. – (Sapa, June 2008)
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