Fertility drugs given cancer all-clear

More and more women are undergoing fertility treatment

Women who take fertility drugs as part of IVF treatment are not at higher risk of ovarian cancer, says the largest study to date.

Fertility specialists use powerful hormones to control a woman's menstrual cycle - and increase the number of eggs that can be harvested for fertilisation.

There had fears that these could either lead to a woman developing ovarian cancer later in life - or the very rapid development of small numbers of cancerous or pre-cancerous cells that might otherwise never cause a problem.

However, the latest review of research, conducted at the University of Pittsburgh, and published in the American Journal of Epidemiology, has found no evidence of a link.

Researchers collected data from eight studies in the US, Denmark, Canada and Australia - which involved 5,207 women with ovarian cancer and 7,705 women without.

No link

Women who had used fertility drugs were no more likely to get ovarian cancer than those who had never used fertility drugs.

Every successful pregnancy reduced the risk of developing the cancer later.

This is excellent news because it probably means that we are not triggering an underlying cancer to explode

Dr Simon Fishel, Care in the Park Clinic

However, women who spent years trying to conceive were 2.7 times more likely to develop ovarian cancer.

This suggests that certain underlying conditions which can cause infertility may also boost the risk of ovarian cancer - although this theory is controversial.

In particular, there was an association between endometriosis - a pelvic condition that causes inflammation and pain - and the cancer.

Women with so-called "unexplained infertility" may also be at risk, suggests the review.

Potential to help

However, other fertility causes, such as problems with menstruation or ovulation, ovarian cysts, blocked fallopian tubes or cervical mucous, were found to have no statistical link with ovarian cancer.

Ovarian cancer is one of the most dangerous, as it is often quite advanced by the time symptoms emerge and doctors can make a diagnosis.

In fact, repeated IVF treatment may come to aid of women who do develop ovarian cancer, as in some cases the repeated ultrasound scanning of the ovaries may detect tumours early.

Dr Simon Fishel, director of the Care in the Park Clinic in Nottingham, was one of the first researchers to suggest a theoretical link between fertility drugs and ovarian cancer, in an article in the British Medical Journal in 1989.

He told BBC News Online: "This is excellent news because it probably means that we are not triggering an underlying cancer to explode."

However, he added: "We will have to look at enough women who are in their 50s to make sure that there is no risk."