Do Fertility Drugs Cause Ovarian Cancer?

Ovarian cancer itself usually begins within the cells at the ends of your fallopian tubes. There’s no single cause of ovarian cancer, but there are many risk factors that could contribute to its development. One such risk factor is the use of fertility drugs.

Fertility drugs work by assisting in the process of ovulation, or the release of an egg from your ovary. While the process itself isn’t thought to contribute to ovarian cancer, these treatments involve various different hormones that may increase your risk.

Recent research

Here’s what the research has to say about some of the most commonly used fertility drugs and the possible links to ovarian cancer:

• Clomiphene citrate (Clomid, or CC). This selective estrogen receptor modulator (SERM) has been on the market since the 1960s, and may be used on its own or in combination with in-vitro fertilization (IVF). Research shows that while there’s a slight increase in ovarian cancer cases in those who took CC, the greatest risk was in those who used the fertility drug for longer than 1 year.

• Gonadotropins. These fertility drugs are used for non-ovulatory disorders, and may sometimes be combined with CC. According to previous studies, ovarian cancer risk increased with the gonadotropin-CC combination.

• Follicle-stimulating hormone (FSH), progesterone, luteinizing hormone (LH). All of these types of hormones used in fertility treatments have shown to possibly be growth factors in ovarian cancer.

Overall, the studies that have looked at potential fertility drugs and ovarian cancer links have been contradictory. Most have also found that the majority of women who take fertility treatments do not go on to develop ovarian cancer.

Research limitations

It’s worth noting that there are limitations to the research done thus far on the link between fertility drugs and ovarian cancer. For one, many women who have used fertility drugs may not be at the average age of onset for ovarian cancer, so it can be difficult to make a definitive link.

Another limitation to the research involving fertility drugs and ovarian cancer development is that fact that many people seeking treatment for infertility may be given more than one drug. Thus, it may be more difficult to determine which fertility drug is the primary culprit in overall cancer risk.

Also, while fertility drugs may increase the overall risk of ovarian cancer, it’s not clear whether IVF treatments are linked to more aggressive cancers.

According to the American Cancer Society (ACS), IVF may be associated with “borderline” ovarian tumors or those with “low malignant potential,” but there are no strong links between more aggressive ovarian cancers and fertility drugs.

Overall, infertility has increased since 1990. However, according to the National Cancer Institute, the incidence of ovarian cancers decreased each year between the mid-1980s to 2017.

Researchers also don’t know for certain whether infertility itself directly increases your risk for developing ovarian cancer, or if related factors are to blame.

For one, not having a pregnancy means you ovulate more. The ACS explains there’s a theory that having more ovulation cycles may be linked to developing ovarian cancer later in life. Pregnancy, as well as taking oral contraceptives, reduces the number of times you ovulate.

Another possible link between infertility and ovarian cancer is the previous, but unsuccessful, use of fertility treatments. Such studies have shown a possible higher risk of using fertility drugs and not conceiving, versus individuals who went on to conceive and have successful deliveries.

Also, if you experience infertility and want to have children, you may be more likely to take fertility treatments than someone who isn’t trying to get pregnant. This could indicate the treatment — rather than infertility itself — could increase cancer risk.

Besides fertility drugs, other known risk factors for ovarian cancer development include:

• inherited gene mutations, such as BRCA1 and BRCA2
• acquired gene mutations, such as HER2 or TP53
• family cancer syndromes, such as Lynch syndrome, which may account for up to 25 percent of all ovarian cancer cases
• age — about half of all ovarian cancers develop in women over 63 years of age
• family history of ovarian or colorectal cancers
• personal or family history of breast cancer
• endometriosis
• having your first child after the age of 35
• never carrying a fetus full-term, which means more ovulation cycles
• smoking
• having obesity or being overweight
• taking hormone replacement therapy

If you think you’re at an increased risk for ovarian cancer, talk with a gynecologist. Your gynecologist may refer you to a genetic counselor for more advanced consideration of your risk factors and fertility options if you are still interested in having biological children.

Along with regular screenings, your gynecologist may recommend one of the following treatments to help reduce your overall risk if you don’t plan on having children:

• oral contraceptives, which may be suitable in reducing ovarian cancer risk in people without inherited gene mutations by half and can have protective effects for up to 30 years
• hysterectomy
• tubal ligation (“getting your tubes tied”)
• bilateral salpingo-oophorectomy, which is a surgery that removes the ovaries and fallopian tubes only

Additionally, it’s important to report any possible symptoms of ovarian cancer to your gynecologist right away, as treatment is most effective when the cancer is caught in its earliest stages. Possible symptoms of ovarian cancer include:

• unusual vaginal bleeding or vaginal discharge (especially after menopause)
• pain in your pelvis, abdomen, or back
• feeling full too quickly when eating
• bloating
• constipation
• frequent urination

Ovarian cancer is the most fatal of all gynecological cancers. While ovarian cancer cases and related deaths have steadily decreased over the last several years, reducing your risk factors can help you prevent its development.

While research into the possible link between fertility drugs and ovarian cancer isn’t conclusive, these treatments are still considered a possible risk factor.

If you’re considering fertility treatments, you should thoroughly discuss the benefits versus possible risk factors with a doctor. They may also consider genetic and familial risk factors in helping you make this important decision.