Scientists believe that a recent fall in the number of postmenopausal women requiring breast cancer treatment may be linked to a drop in hormone replacement therapy (HRT) use.
Almost 46,000 people are diagnosed with breast cancer every year in the UK and the vast majority of these develop the disease when they are past their menopause.
Cancer Research UK scientists conducted an analysis of breast cancer rates compared with HRT use in recent years and found that there is a significant link between the two.
The risk of breast cancer for women in their 50s fell by 14 per cent between 1999 and 2005, according to lead researcher Professor Max Parkin, whose findings are published in the European Journal of Cancer.
He said that while he cannot be sure that the drop in breast cancer rates is the direct result of women giving up HRT, "the parallel is striking".
The professor added that it will be "interesting to see if this decline continues over the next few years".