Researchers believe that there could be a link between a drop in the number of middle-aged women taking hormone replacement therapy (HRT) and a fall in breast cancer rates.
According to research published in the European Journal of Cancer, in the year 2000 approximately 40% of women aged 50–54 were taking HRT, but this figure dropped to 20% in 2006. At the same time, the figure for women aged 55–59 fell from 35% to 15%.
As HRT use declined, so did the breast cancer rate, falling 0.8% a year in women aged 50–59 since 1999.
However, among women in their 60s the breast cancer rate increased by 24% from 1999 to 2005, but this is thought to be as a result of a breast cancer screening programme detecting more tumours.
Since 2003 the rate has fallen among women aged 60–64.
A number of women decided to stop using HRT following research by the Women's Health Initiative study in the USA and the Million Women Study in the UK, which found that users had an increased risk of developing breast cancer.