Women are being advised to avoid the long-term use of contraceptives and HRT in a bid to cut the risk of breast cancer.
Experts have warned that one in seven women will develop breast cancer if present health trends continue.
A study led by Professor Gareth Evans on behalf of the Genesis Breast Cancer Prevention Centre, Manchester, found that the risk to women who carry gene mutations that can lead to the disease has increased dramatically in the past 60 years.
One in 10 women in the UK currently develop breast cancer by the age of 80, but researchers fear this may increase to one in seven by 2024 unless lifestyle changes are made.
Professor Evans recommended women should plan families earlier, avoid long-term use of female hormones in contraceptives and HRT, and embark on a healthy lifestyle by exercising and maintaining a healthy weight.
The consultant at St Mary's Hospital and Christie Hospital, both in Manchester, said: "In 1984 only one in 13 women were projected to develop breast cancer in their lifetime. In 2004 this reached one in 10 and, if the rates rise as they are currently doing so, it is predicted that by the year 2024 one in seven to eight women will develop breast cancer by 80 years of age in the UK."