Fertility drugs ‘link’ to cancer
Reported December 14, 2008
Fertility drugs have been linked to an increased risk of womb cancer in women treated three decades ago.
The discovery was made by Israeli scientists who looked at cancer incidence in 15,000 women 30 years after they gave birth.
Of 567 women given drugs to induce ovulation, five had developed womb cancer – about three times the incidence level for women whose fertility was not artificially enhanced.
For 362 women who took the drug clomiphene, which tricks the body into making extra eggs by blocking hormone activity, the risk was increased more than four times.
The team, led by Dr Ronit Calderon-Margalit at Hadassah-Hebrew University in Jerusalem, also found smaller but significant increases in rates of breast cancer, malignant skin cancer, and non-Hodgkin’s lymphoma linked to the drugs.
However, no association was seen with ovarian cancer, which some previous studies have linked to fertility treatments.
The research was highlighted in New Scientist magazine.
Jodie Moffat, health information officer at the charity Cancer Research UK, said it was difficult to draw any firm conclusions from the results.
“This study didn’t include a detailed history of fertility drug use, and the number of women who developed uterine (womb) cancer was very small,” she said.
However Dr Calderon-Margalit said the evidence of a link made “biological sense”. Tamoxifen, a breast cancer treatment which, like clomiphene, reduces sensitivity to oestrogen, was known to increase the risk of womb cancer.