Why are women under 50 not routinely invited for breast screening?

Women under 50 are not currently offered routine screening. Research has shown that routine screening in the 40 to 50 age group is less effective. As a woman goes through the menopause the glandular tissue in her breast "involutes", that is to say, the proportion of fat in her breast increases. This makes the mammogram easier to interpret.

However the DMIST study has shown that digital mammography is better for screening younger women and women with denser breasts, and is equally effective as film mammography in older women.

So the programme is now being gradually extended to women aged 47 to 49, as well as to those aged 71 to 73. The age extension of the programme is expected to be complete by 2016.

It is important to note that women of any age can ask their GP to refer them to a hospital breast clinic if they are concerned about a specific breast problem or otherwise worried about the risk of breast cancer. Although this is not part of the NHS Breast Screening Programme, the same techniques are used in both breast screening units and hospital breast clinics for diagnosing breast cancer and many staff work in both settings.