Later menopause ‘raises the risk of breast cancer’

WOMEN who go through a later menopause are at a greater risk of breast cancer, British scientists have warned.

Each year past the age of 50 raises the odds of the disease by 6 per cent, they say.

It is thought that the delay increases the amount of time a woman is exposed to oestrogen, a sex hormone known to fuel tumours.

The researchers said those who go through ‘the change’ later in life should be aware of the link and be extra vigilant at checking their breasts for early warning signs.

Breast cancer is the most common form of the disease in Britain and one in eight women will be told they have it in their lifetime.

Some 50,000 cases are diagnosed each year – with 12,000 deaths – and most cases occur after the menopause. The study, led by Cambridge and Exeter University experts, also has implications for younger women.

It could lead to a genetic test that tells a woman when she will go through the menopause – helping her start a family before she stops producing eggs.

The British-led study examined the DNA of almost 70,000 European women, including some from the UK. Scientists from 177 universities, hospitals and institutions around the world analysed data and identified 44 genes linked to the timing of the menopause.

Most of the genes operate by repairing damaged sections of DNA in a woman’s eggs, keeping them healthy. However, if the genes are faulty the eggs can perish, hastening the onset of the menopause.

Learning more about such genes could lead to drugs that ensure eggs are kept in good health. These could be used to prevent women going through the menopause early – or even delay it, allowing them to have babies later in life. Scientists may also be able to develop a genetic test to predict the date of her menopause.

But while these tests and drugs are still in the future, the study has some immediate implications.

The average British woman hits the menopause – defined as the time when her periods have stopped for 12 months – at around 50. The researchers calculated that each year beyond this increases the risk of breast cancer by 6 per cent.

So while the average woman has a 12.5 per cent risk of developing breast cancer in her lifetime, it rises to 13.25 per cent after a delayed year. If the menopause starts at 55, her odds of breast cancer rise to 15.7 per cent.

Dr Anna Murray, of the University of Exeter, said: ‘If you have a late menopause, it might help to know about this slightly increased risk of breast cancer and help you keep on top of it.’ Women who go through the menopause before 50 have a lower than average risk of breast cancer. However, an early menopause is linked to heightened odds of osteoporosis, diabetes and heart disease, the journal Nature Genetics reports.

Dr Edward Morris, of the Royal College of Obstetricians and Gynaecologists, said the findings were ‘reassuring’.

Yinka Ebo, of the charity Breast Cancer Now, said the increased risk of the disease is ‘small but real’.