Risk Factors

  • Being female is the single biggest risk factor for breast cancer
  • Breast cancer risk increases with age: the older the woman, the higher the risk
  • A significant family history
  • The risk is greater in women who consume a high fat diet
  • Women with no children or having their first pregnancy after the age of 30 years
  • Commencing menstrual periods before the age of 11 years
  • Menopause occurring after the age of 55 years
  • Smoking and alcohol intake may also increase risk

There is some evidence that certain types of Hormone Replacement Therapy (HRT) and contraceptive pill may slightly increase your risk of breast cancer. If you are at all concerned about HRT/pill use you should discuss this with your GP. There is no evidence that women on HRT/pill require more frequent mammograms than received through routine screening.

Women with close relatives diagnosed with breast cancer may be more at risk, although it is important to bear in mind that only around 5% of breast cancers are family history related. If you are concerned about a family history of breast cancer you should discuss this with your GP. Take as much information as you can about your blood relatives on both your mother’s and father’s sides of the family who have had a cancer diagnosis.

For each family member who has had cancer your GP needs to know:

  • What relation they are to you and to each other
  • Which cancer they had
  • How old they were when they had it
  • If they are still alive, or when they died

If they feel that your family history is significant they will refer you to a family history clinic/cancer genetics centre for further assessment.  They can arrange regular surveillance for you, even if you are younger than the screening age and can also involve genetics testing if appropriate.

There is evidence that breastfeeding for more than five months in total (one or more babies) can reduce a woman’s risk of breast cancer, compared to women who do not breastfeed. It also shows that the longer a woman breastfeeds, the greater the protection. However, many women are either unable to breastfeed or choose not to.

There are other ways of decreasing your risk of developing breast cancer, such as maintaining a healthy weight and staying within the recommended guidelines for drinking alcohol. But it’s important to remember that the biggest risk of getting breast cancer comes from being female and getting older.

Breast pain is very common in women of all ages. For example, approximately two out of three pre-menopausal women will experience it at some time in their lives. Having breast pain does not increase your risk of breast cancer. However, it is still important to be breast aware and go back to your GP if your pain is persistent, unusual or you notice any other changes in your breasts.

See ‘I have breast pain - am I at higher risk?’ for further information.