The Pill and Cervical Cancer: What You Need to Know

When Amanda Saxon found out her pap came back abnormal, her doctor told her not to worry. A woman her age would have no trouble clearing the human papillomavirus, the likely culprit. So the then-21-year-old college student from Tampa, Florida, went back to her normal routine. Her pap results, on the other hand, did not.

After a few years of “some clear, some not” annual exams, her pap smears showed that the situation was getting worse. The results revealed high-grade dysplasia, which means there were significant changes to the cells of her cervix, putting her at great risk for developing cervical cancer. Again, Saxon’s doctor assured her that everything would be fine, but that a closer look was needed.

A series of exams and invasive biopsies followed over the next year. All of them had disappointing if not frightening results. If the problem continued, Saxon would need what’s called a cold knife cone biopsy, which is a surgical procedure to remove cervical lesions.

“My husband and I were making plans to start a family,” Saxon recalled. “As if the cancer threat wasn’t scary enough, what about my fertility? I wanted to know everything I could about why this was happening and if there was anything I could do to get it to stop.”

That’s when she started doing her own research. Would changing her diet help? What about exercise? If the problem was that she wasn’t fighting the virus, could she jump-start her immune system somehow? In the course of digging, she came across an online forum that said she should stop her hormonal birth control pills, which she had been taking regularly since age 17. Then, she dug deeper and found numerous mentions -- on reputable sites, such as the National Cancer Institute and the Guttmacher Institute -- of the birth control pill’s link to cervical cancer. She mentioned her findings during her next appointment, but her doctor couldn't say whether that might be a reason she wasn’t clearing the infection.

“She said there was no evidence that stopping the pill would help,” Saxon said. “She suggested I stop Googling stuff because I was just freaking myself out.”

Can the Pill Really Suppress Your Immune System?

If you do a quick Google search for the question above, you'll get more than 400,000 results, many of which are from crowd-sourced (read: unreliable) ask boards like ChaCha or Yahoo! Answers. Perhaps worse -- oddly -- you’ll come across the vague yet startling information about the pill’s possible effect on the immune response and cervical cancer on reliable sites, as Saxon did.

Women are wondering about this, yet there doesn't seem to be straight advice about what to do -- even when they ask their doctors about it. “And when that happens, it’s often because there just isn’t a clear answer yet,” said Dr. Kari Braaten, an obstetrician and gynecologist at Brigham and Women’s Hospital in Boston.

“No one would say that the pill by itself makes you more likely to contract HPV; nor does it make you more susceptible to other infections like the cold or flu,” said Dr. Jen Gunter, an ob-gyn in the San Francisco Bay Area. And although there is evidence linking oral contraceptives to a slight increase in risk for cervical cancer, experts disagree on what’s behind it. “It’s controversial," Gunter said. "People are very much divided on what’s actually going on." It could be a matter of riskier sexual behaviors: For example, a 2012 study found that women on the pill were less likely to use condoms, which are known to lessen exposure to HPV.

Contrary to what Saxon’s doctor told her, however, there is at least some evidence that long-term use of the pill plays a role in viral persistence or repeated reactivation of a latent virus, according to Dr. Xavier Castellsagué, director of the WHO/ICO (Catalan Institute of Oncology) Information Centre on HPV and Cervical Cancer in Barcelona, Spain. In 2002, the International Agency for Research on Cancer published a review that found a strong presence of cervical pre-cancers and cancers among HPV-positive women who used the pill consistently for five years or longer, and research since then has backed it up. There was no increase for women who used the pill for four years or less.

“It’s obvious it is a co-factor,” Castellsagué said, even if there is no certainty about the mechanism.

It is important, though, to stress that Saxon’s case and others like it are uncommon. Saxon’s doctor was right to assume at every step that Saxon would clear it on her own.

“Even the biopsies themselves can stimulate a positive immune response in the cervix and help clear it,” Gunter said.

HPV is the most common sexually transmitted infection in the United States. More than half of sexually active people will get one or more strands of the virus and clear it in their lifetimes, and at any given time, about 43 percent of women are infected with HPV, according to the National Cancer Institute. “Most women test positive for it by age 23,” Gunter said.

Almost all cervical cancers start as HPV, but scientists are still studying why some women infected with HPV develop cancer while most have no effects at all. Ninety 90 percent of those infected with the virus clear it within two years, Castellsagué said.

It’s impossible to say why Saxon ended up in the remaining 10 percent who develop persistent infections and the cervical lesions that, if left untreated, can turn into cancer. She was young and otherwise completely healthy. And that’s the real problem: There is still no way of knowing, on an individual level, who will clear the virus and who will need further treatment.

The development of cervical cancer, as with other forms of cancer, is a complicated dance of genetics, environment and several other contributing factors. High-risk or “oncogenic” strains of the virus are more likely to lead to cervical cancer. (Two of these, types 16 and 18, are responsible for almost all HPV-related cancers and for which there is a vaccine.) But there are many other known factors, aside from the possible link to the pill.

While it’s true that your individual genetics play a role in whether you can clear the virus, “The immune system is key here,” Castellsagué said. The thinking is that a suppressed immune system is what allows the virus to stick around and cause trouble, which is why women with HIV or those who take immunosuppressive drugs for autoimmune diseases are at greater risk for cervical abnormalities. Similarly, smokers are twice as likely to have problems with persistence because of the effects cigarettes have on immunity.

The Bottom Line

Medical advice represents a weighing of the benefits and the risks of a certain tactic based on what’s most common or most likely to happen.

“I would never suggest a patient stop her birth control simply because she wasn’t clearing HPV," Braaten said. "So far, what we know for sure is that any complication associated with the pill -- including any effect on your immune system -- is exacerbated during pregnancy. And we know that the vast majority of HPV-infected women will clear it on their own.” Meaning: in most cases, pregnancy is both the bigger and more likely threat.

If you’re on the pill now, don’t panic. Oral contraceptives remain among the safest, most effective medications on the market. As long as you’re getting a clean bill of health during your annual checkup and regular pap smears, there is no reason to worry. Your best bet for preventing a problem down the road is to talk to your doctor about the HPV vaccine -- not to quit the pill, no matter how long you’ve been on it. And remember, the pill does nothing to protect you against sexually transmitted infections, so don’t skip condoms!

For women struggling with a lingering, trouble-causing virus, the official bottom line is that there’s not enough evidence to say that going off the pill will definitely help you clear the infection. But it also couldn’t hurt, as long as you use another method of reliable contraception.

Saxon ultimately chose to make the switch to condoms after it became clear she would need the surgery. “It was just so frustrating," she said. "Every time, [the doctor] said it would clear up, but things only got worse. I felt like even if there was only a small chance stopping the pill might help my immune system fight the infection better it would be worth it.”

While there is no way of pinpointing what difference the switch made, Saxon can count at least one expert in her corner: “Her situation is very uncommon, but it does happen," Castellsagué said. "In my opinion, once you have some cervical abnormality for longer than a year and it’s not going away, it’s a good idea to switch to another method of contraception.”

Saxon may be an anomaly, but the fact is she is one of the people who, for whatever reason, had difficulty getting the virus under control. If there is a smidgen of a chance the pill may play a role in fighting what could have been cancer, why would I even take that chance? she asked.