It all started on the NBC’s Today show, with the announcement of E! news anchor and reality show star Giulana Rancic. The 36-year-old revealed that she had breast cancer when her fertility doctor urged her to have a mammogram before receiving more in vitro fertilization (IVF) treatment.
Speculation then rose on whether her fertility treatment was actually connected with the increased risk or cause of breast cancer.
Hormones involved in IVF include estrogen, progesterone, follicle-stimulating hormone and luteinizing hormone. While high estrogen levels may be associated with cancer, experts say there is no strong evidence that IVF drugs have anything to do with causing or increasing the risk for breast cancer. It may actually even be preventing cancer, they note.
In theory, the tumor of a woman with breast cancer could be stimulated to grow with increased levels of estrogen and progesterone, but this would only hold true for women who are already pregnant because their hormone levels would naturally go up throughout the pregnancy.
Notes Adrian V. Lee, professor of pharmacology, chemical biology and director of the Women’s Cancer Research Center at the University of Pittsburgh Magee-Women’s Research Institute, the largest study in Sweden -- of 25,000 women who underwent IVF compared to 1.4 million who did not -- showed a 25 percent risk reduction in breast cancer, and a 40 percent risk reduction in cervical cancer in those who had IVF.”
Samantha Pfeifer, M.D., chair of the practice committee at the American Society for Reproductive Medicine, says that studies have been linking exposure to estrogen and progestin of women in their 50s and 60s with increased risk for breast cancer. But these women aren’t exposed to estrogen via fertility drugs, therefore nullifying any possible association.