The number of women under the age of 50 who are diagnosed with breast cancer is on the rise, a charity has warned.

In 2010, 10,068 women under the age of 50 in the UK were told they had the disease – 2300 more than the number diagnosed in 1995, Cancer Research UK said.

The charity said one in five breast cancer cases were now among women under the age of 50.

While the reason behind the increase is unclear, the charity suggested a rise in alcohol intake, the use of the contraceptive pill and women having fewer children and in later life could be to blame.

Routine screening for breast cancer is offered to women aged 50 to 70 but recent changes to the programme will also see those in their late forties invited.

Sara Hiom, Cancer Research UK's director of health information, said: "Breast cancer is more common in older women but these figures show younger women are also at risk of developing the disease.

"Women of all ages who notice anything different about their breasts, including changes in size, shape or feel, a lump or thickening, nipple discharge or rash, dimpling, puckering or redness of the skin, should see their GP straight away, even if they have attended breast cancer screening."