Choice Ireland

breakingnews.ie
26th October 2011

Taking the Pill for 10 years can almost halve a woman’s risk of ovarian cancer, new research has shown.

Using oral contraceptives for any length of time was associated with a 15% reduction in cancer risk.

The risk fell further the longer a woman was on the Pill. After a decade, it had fallen by 45%.

However, protection against ovarian cancer had to be balanced against a greater risk of breast cancer, said the researchers.

In 100,000 women, taking the Pill for 10 years or more was expected to lead to 50 more breast cancers but 12 fewer ovarian cancers.

Pregnancy was also found to reduce ovarian cancer risk. Women who had been through a full-term pregnancy were 29% less likely to develop the disease than women who had never been pregnant.

The findings emerged from the ongoing Epic (European Prospective Investigation of Cancer) study investigating dietary and lifestyle links to cancer in more than half a million European men and women.

Scientists are not sure why the Pill and pregnancy help to prevent ovarian cancer. One theory is both alter levels of hormones that affect disease risk.

Ovarian cancer is the fifth most common cancer among UK women, with more than 6,500 cases diagnosed each year.

It has been called the “silent killer” because often the disease is not detected until an advanced and lethal stage.

Risk factors for ovarian cancer include smoking, obesity, and having close relatives who have developed the disease.

Dr Naomi Allen, a member of the Epic team based at Oxford University, said: “Ovarian cancer is difficult to detect and so prevention is key to saving women suffering from the disease.

“These results are important because most women don’t know that taking the Pill or getting pregant can help reduce their risk of ovarian cancer later in life.”

The study, published in the British Journal of Cancer, was part-funded by the charity Cancer Research UK.

It showed that taking the Pill for more than 10 years led to the biggest reduction in ovarian cancer risk, followed by getting pregnant and having more than one child.

Among women who used the Pill for a year or less, the number likely to develop ovarian cancer each year was around 28 per 100,000.

Taking the Pill for at least 10 years reduced the number of cases to 15 per 100,000.

Having at least one full-term pregnancy lowered ovarian cancer incidence from 34 per 100,000 to around 24 per 100,000.

Dr Richard Edmondson, a Cancer Research UK women’s cancer expert from the University of Newcastle, said: “Women may be reassured to know that the oral contraceptive is not only an effective contraceptive but can have the added benefit of reducing their risk of ovarian cancer.

“This is however balanced against a slightly increased risk of developing breast cancer. To put this in context, it is estimated that if 100,000 women use the pill for ten years or more there will be 50 more breast cancers than would have otherwise occurred, but 12 fewer ovarian cancers.

“This may be particularly important for women with an increased risk of ovarian cancer in their family.”

Sara Hiom, director of health information at Cancer Research UK, said: “These days it is not uncommon for women to have fewer children or none at all. Women tend to be unaware that these reproductive factors have a protective effect on their risk of ovarian cancer.

“Nobody can expect women to start living like their Victorian counterparts to reduce their risk of the disease. But there are other things that can be done to lower the risk of ovarian cancer like stopping smoking and maintaining a healthy weight.

“As with most cancers, the risk of developing ovarian cancer increases with age – most cases are in women who are past their menopause. Inherited faulty genes can also play a significant role, and women who think they may have a family history should discuss this with their doctor.

“Treatment for ovarian cancer is better if the disease is caught as early as possible. So all women should be aware of the signs of ovarian cancer like pain in the lower tummy, bloating, increased tummy size, difficulty eating or feeling full. If these symptoms are new and happen on most days then it’s worth getting checked out by your doctor without delay.”