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Doctors: IVF not to blame for Rancic's breast cancer

Dr. Nancy Snyderman talks with TODAY's Ann Curry about whether there's a connection between in vitro fertilization and breast cancer.

Giuliana Rancic’s recent diagnosis of breast cancer at age 36 has generated a lot of emotional support for the E! host -- and some worries about the connection between fertility treatments and the disease.

During an interview with TODAY’s Ann Curry Monday about her efforts to have a baby, Rancic revealed that her cancer was discovered through a mammogram ordered up by her fertility specialist. Rancic, who has no family history of breast cancer, said she was dragged “kicking and screaming” to the breast screening after the specialist insisted on the mammogram before he would start a third cycle of in vitro fertilization, or IVF.

“He said, 'I don't care if you're 26 or 36, but I will not get you pregnant if possibly there's a small risk that you have cancer because the hormones will accelerate the cancer,'" Rancic told Curry Monday.

That advice may have helped save Rancic’s life, but it raised worries among some women. Could Rancic's breast cancer be connected in any way to the fertility treatment she had undergone?

 "No," said TODAY's Dr. Nancy Snyderman in a follow-up on the show Wednesday. The hormones used in both in vitro fertilization and birth control pills have been studied and "there's no known cause and effect," she told Curry. "What we do know is that women who are older usually ask for IVF because they're having a harder time getting pregnant -- and women who are older have a higher chance of getting breast cancer, so there is an age relation, but not a hormonal relation."

On Tuesday Rancic underwent a lumpectomy in both breasts and is now recovering.  Rancic was fortunate her doctor insisted on the screening. Mammograms are not a standard part of fertility treatment in patients her age, said Dr. Mark Perloe, medical director at Georgia Reproductive Specialists.

 “We certainly want people to have a full health evaluation before beginning fertility treatments,” Perloe added.  “But we wouldn’t recommend a mammogram unless there was a family history of breast cancer or a genetic risk.”

E!'s celebrity news personality Giuliana Rancic tells TODAY's Ann Curry that she has breast cancer, a new struggle in her journey to have a baby.

Breast cancer is unusual in women under 40 -- only 5 percent of all cases -- although the tumors can be faster-growing and harder to treat.

While many supporters on The Clicker Facebook page praised the benefits of mammograms, several commenters feared that "bad estrogen" or other hormones may have been connected to Rancic's diagnosis.

Hormones used in IVF cycles include estrogen, progesterone, follicle-stimulating hormone, and luteinizing hormone.

Despite the hormone paranoia, it's even possible that IVF might be protective.

“The evidence is that IVF has no effect or lowers incidence, said Adrian V. Lee, a professor of pharmacology and chemical biology and director of the Women’s Cancer Research Center at the University of Pittsburgh’s Magee-Womens  Research Institute. “The largest study in Sweden -- of 25,000 women who had IVF compared to 1.4 million without  -- showed a 25 percent reduction in breast cancer and a 40 percent reduction in cervical cancer in those who had IVF.”

Theoretically, Perloe said, if a woman had breast cancer, higher levels of estrogen and progesterone could stimulate the tumor to grow. But that would be true even if the woman got pregnant on her own because hormone levels rise as a pregnancy progresses.

"My concern is that this is going to cause a lot of people to be afraid," Perloe said. "My advice to anyone who has concerns is to speak to their doctor and learn to do breast self-exams -- and to check to see if anyone in their family had cancer before thet age of 40."

As for routine mammograms in infertile women aged 26 to 36, Perloe said, that would be a mistake. That's because mammograms come with some radiation exposure.

"So you have to balance the risk of exposure to radiation from testing against the likelihood that there might be something there," Perloe said.  

When women should begin mammogram screening is controversial. The U.S. Preventive Services Task Forces recommends breast cancer testing start at age 50, although the American Cancer Society advises yearly mammograms beginning at age 40 for women with an average risk.

So, women with infertility problems can relax, about their breast cancer risk at least. IVF treatments may not guarantee a baby, but they won't worsen your odds of developing cancer, doctors say.

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