TV host Giuliana Rancic has long been open about her struggles with infertility. In 2011, she announced that she would be fighting an even more difficult battle -- this time with breast cancer.
Rancic's own doctor even refused to continue her fertility treatments, citing concerns that high doses of hormones involved in the treatments could speed the growth of her cancer.
The news re-triggered a longstanding debate within the reproductive health community:Does in vitro fertilization (IVF) increase the risk of ovarian, breast, and other reproductive cancers?
Until now, the evidence has been highly anecdotal, and murky at best. Now, a new Dutch study sheds more light on the issue. According to the study, IVF may double the risk of developing ovarian cancer.
Is this scary news for IVF patients? Absolutely. But things turn out to be a bit more complicated than you might think. Here's what you need to know about the link between IVF and ovarian cancer.
The Connection Between IVF and Reproductive Cancers
Researchers looked at 25,152 Dutch women with a history of infertility. 19,146 participants underwent IVF, with the remainder foregoing the procedure. Fifteen years after an initial IVF treatment, women who had undergone IVF were twice as likely as those who had not to experience ovarian cancer.
A deeper dive into the research, however, reveals that the risk might not be as frightening as it seems. Consider the following:
- The increase in ovarian cancer was driven primarily by “borderline” ovarian tumors. These tumors, sometimes called tumors of low malignant potential, are less likely to spread to other regions of the body, and are more responsive to treatment.
- Just 30 women in the IVF group experienced invasive ovarian cancers. Though this was slightly more than experienced cancer in the non-IVF group, the difference was not statistically significant. That means there is no conclusive scientific proof linking IVF to invasive ovarian cancer.
- The risk of developing ovarian cancer was still quite low. Women over the age of 55 have a .0.45% chance of developing some type of ovarian malignancy, including the less dangerous borderline tumors. In women over 55 who have undergone IVF, the risk is 0.71%. Even the high hormone doses associated with IVF still produce a less than 1% chance of cancer.
Infertility and Reproductive Cancer
Previous research suggests that women who experience infertility already have a higher-than-average risk of developing reproductive cancers, including ovarian cancer.
The latest study controlled for those risks, so the cancer incidence in study participants cannot be explained solely by infertility, or infertility-causing diseases.
However, in women with untreated infertility, the link between infertility and cancer suggests the importance of treating infertility. Even if you opt not to pursue IVF, getting tested can reveal medical conditions that affect not only your fertility, but also your health.
How Could IVF Cause Cancer?
Cancer is a complex illness that is still not well-understood. Cancer research points to a number of different causes and risk factors, ranging from infectious diseases to environmental toxins.
Subtle alterations in normal cells can cause them to grow out of control, triggering cancer. Cancer cells are challenging to kill precisely because they are so similar to normal cells. Few studies have directly assessed how IVF could cause cancer. Research on other cancers and medications, however, has conclusively demonstrated that high-dose hormonal therapies can trigger cancer. This is likely because these treatments alter cell growth patterns, “training” the cells to grow out of control, and later causing cancer.
Hyperstimulation of the ovaries may also play a role. IVF drugs aim to get the most out of each cycle by causing the ovaries to produce multiple eggs. Over time, this may cause subtle mutations in epithelial cells that eventually lead to ovarian tumors.
What Can I Do to Reduce My Risk?
The study did not assess whether specific harm reduction strategies helped women avoid ovarian cancer. However, based on what we already know about cancer, we can suggest some options that may reduce your risk of developing ovarian cancer. Those include:
- Trying other strategies before pursuing IVF. Not all cases of infertility are best treated with IVF. Less costly and invasive treatments may work just as well, particularly if the cause of your infertility can be identified.
- Ask your doctor to use the lowest possible doses for hormones.
- Tell your doctor about any family history of breast or ovarian cancer, and consider getting tested for the breast cancer gene. If you do not know your family history, ask your parents or grandparents.
- Work with a fertility clinic that has a high success rate. Getting pregnant sooner means fewer cycles of IVF, and therefore less exposure to hormones that may trigger cancer.
How Should I Make the Decision?
The best source for information on your individual cancer risk is your doctor. We strongly encourage all patients not to rely on hyped-up media reports, or on scare tactics from friends and family. No matter how many fertility treatments you undergo, your cancer risk is vanishingly small.
What if you're still concerned? For many couples, a small increase in the risk of cancer is worth the chance to have a biological child. If you're unsure, here are some questions you can ask yourself before making the decision:
- Do I have a family history of cancer?
- How comfortable am I taking risks?
- How important is it to me to have a biological child? Would adopting or not having a child be an option?
- How many cycles of IVF am I willing to undergo?
- How good are my odds of success, according to my doctor?
- Have I tried other, less invasive, treatment options?
- What is the success rate for the clinic I am considering?
Talk it over with your partner and your doctor. IVF remains a great and safe option that has been around for decades. And the IVF of today is safer than ever, with a higher success rate than ever before.
Ultimately, you'll have to decide whether the risk is worth the possible reward, and no one can tell you what the “right” decision is. There is no right decision -- only the right choice for you and your family.