Skip to main content
search here
username password
Macmillan and Cancerbackup have merged. Together we provide free, high quality information for all.
How we produce our information|
Each year, about 6600 women in the UK are diagnosed with ovarian cancer. The causes are not yet completely understood, but some factors (known as risk factors|) are believed to increase a woman’s chance of developing epithelial ovarian cancer, the most common type.
As with many cancers, the main risk factor for ovarian cancer is age (being over the age of 50). Other possible risk factors include a strong family history of ovarian or breast cancer, obesity, use of hormone replacement therapy (HRT), and infertility and fertility treatments.
Other factors (called protective factors|) may reduce a woman’s risk of ovarian cancer such as having children, using the contraceptive pill and breastfeeding.
A risk factor is something that increases your chances of developing a health condition such as cancer. For example, smoking is the best known risk factor for lung cancer. Age is another risk factor for many cancers. Most people who develop cancer are over the age of 65. Having a particular risk factor does not mean you definitely will get cancer, just as people without any known risk factors can develop cancer.
The risk of developing ovarian cancer is very low in young women and increases as women get older. Over eight out of ten (85%) ovarian cancers occur in women over the age of 50. Most ovarian cancers occur in women who have had their menopause.
Women who have not had children are slightly more likely to develop ovarian cancer than women who have, although the risk is still very low.
Research has shown that drugs used in fertility treatment may slightly increase the risk of developing ovarian cancer. However, other research doesn’t support this. It has also been suggested that it is being infertile that increases ovarian cancer risk, rather than any treatment you may have for it. There is more research going on to try to clarify this.
Having the condition endometriosis, in which the tissue that normally lines the womb builds up in other parts of the body, may increase your risk of ovarian cancer.
Only a small number (about 5-10 in 100) of ovarian cancers are thought to be caused by a faulty gene| that runs in the family. Women who have had breast cancer| have an increased risk of ovarian cancer. This is because breast and ovarian cancer can be caused by the same faulty genes.
A strong family history |of ovarian, breast or bowel cancer also could mean there is a faulty gene in your family. However, having one or even two family members with cancer does not necessarily mean you carry an inherited faulty gene, and carrying a faulty gene does not mean you will definitely get cancer.
If you are concerned about a family history of ovarian cancer, you might find it helpful to read our 'Are you worried about...ovarian cancer?' factsheet. You can also talk to your GP about your family history and whether it would be helpful to see to a genetic counsellor, family cancer clinic or cancer specialist.
If you are worried about the occurrence of breast or ovarian cancer in your family and whether there might be an inherited genetic link, OPERA| (Online Personal Education and Risk Assessment) is an online interactive software program that will offer you personalised information and support in the comfort of your own home.
The following may reduce the risk of ovarian cancer:
View Q&As on this topic
Posted by Christine1
Posted by bob jk
Posted by GRAEME.
If you have any questions about cancer, need support or just want someone to talk to, ask Macmillan.
Browser does not support script.