London: An increasing number of women are being diagnosed with womb cancer because they are having fewer children or none at all.
Today, 7,530 women are annually diagnosed with the disease, compared to 4,175 in 1975.
Doctors say that women choosing to have fewer children, or not having any -- often in favour of pursuing their careers -- is one of the main causes of the increase, reports the Daily Mail.
Doctors also attribute the rise to increasing rates of obesity which can double the chances of developing a tumour.
Around 1,700 women die from cancer of the uterus every year, show figures from charity Cancer Research, Britain.
They reveal that 19 in every 100,000 women develop the disease, compared with 13 per 100,000 in 1975, a rise of almost 50 per cent.
It is the fourth most common form of cancer in women, and rates have increased faster than for any other form of the disease apart from malignant melanoma, a form of skin cancer.
Womb cancer usually occurs after the menopause between the age of 60-69.
But experts say women are more at risk from developing it when there are higher amounts of oestrogen in their blood.
Levels of the hormone are lower during pregnancy, so women who have fewer children are exposed to the chemical for a longer period of time.
Those who are overweight or obese also have much higher levels, because fatty tissue converts other hormones into oestrogen.
Doctors believe obesity accounts for between 30-50 per cent of all cancers of the womb - but they do not offer figures for the number of tumours they believe are caused by having fewer children.
Jessica Harris, health information officer at Cancer Research, said: "Women are more exposed to womb cancer when there are higher levels of oestrogen in their blood."
"This obviously changes during their menstrual cycle but it will also decrease when women are pregnant," said Harris.
"This means that those who have more children have less time over their lives when they are exposed to the risk," she said.
Latest data shows that every year 7,530 women are diagnosed with the disease, compared to 4,175 in 1975.
According to official statistics, one in five women have not had a baby by the time they are 40, twice as many as 20 years ago.
They also have smaller families, with one in 10 women having more than four children, compared to one in five 20 years ago.