The long-term study conducted by Israeli scientists at Hadassah-Hebrew University in Jerusalem showed that drugs that are commonly prescribed to induce ovulation in women to promote conception are not completely safe for woman's health.
As much as 15,000 women from Israel were monitored after childbirth to find the effects of IVF drugs. The findings show that women, who took ovulation-inducing drugs were three times as likely to develop cancer of the womb. Out of the 567 female participants, five were found to have uterine cancer, which indicates a risk three times higher than of women who didn't undergo treatment with these drugs.
Also 362 women, who reported taking clomiphene, a fertility drug that acts by encouraging woman's body to produce several eggs, were found to have four times increased risk of developing womb cancer. Although the risk is considered to be quite small, the further study is needed to investigate the effects of these fertility drugs.
Clomiphene is usually prescribed to be taken for one five-day cycle a month. It activates follicle-stimulating hormones, making woman's ovaries release one or more eggs. If ovulation was successful and an egg meet sperm, the chances of conception are very high.
Dr Ronit Calderon-Margalit, the leading researcher of the study, said that the results may be significant because previous research showed that tamoxifen, a commonly used drug in breast cancer treatment, which like the clomiphene works by interfering in the activity of the oestrogen, is also a risk factor for developing womb cancer.
Experts claim that the numbers are small to prove the risk, but women undergoing fertility treatment need special attention and risks should be evaluated.