abstract: Too Early To Determine Cancer Risk from Infertility Treatments

Too Early To Determine Cancer Risk from Infertility Treatments

As more and more women wait to have children, the use of fertility drugs is rapidly rising, along with concerns about the possible association with increased risk of certain cancers, primarily of the breast, ovary, and uterus.

Such interest was on display when Elizabeth Edwards, the wife of former Sen. John Edwards, died from a recurrence of breast cancer in 2010, years after she had used fertility treatments. Researchers agree that the issue is important, given the millions of women who have been treated with fertility drugs. By one estimate, that number will climb to 7 million by 2025. 

But the findings from the few studies that have tried to address the issue have been mixed. Most have been conducted outside the U.S., primarily in European countries with centralized health care systems that can track pharmacy and cancer registries. These studies can have methodological limitations, but researchers say the largest drawback is that, usually, it is too early to tell whether an association exists, especially for drugs used for in vitro fertilization (IVF). 

“We are just really now getting into an era where we have enough women who are in the right age range to be able to evaluate their cancer risk,” said Louise Brinton, Ph.D., M.P.H., chief of the hormonal and reproductive epidemiology branch of the Division of Cancer Epidemiology and Genetics at the National Cancer Institute.

But it won’t ever be completely clear whether these drugs cause even a slight increase in cancer risk, says Jennifer Litton, M.D., an assistant professor in the department of breast medical oncology at the University of Texas M. D. Anderson Cancer Center in Houston. “Infertility itself is a risk factor for increases in breast and ovarian cancers, so it is going to be difficult, if …(Blogger's Note: to read further subscription required $$$)