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 $$$)
