Women's Health

Low-Dose Aspirin May Cut Ovarian Cancer Risk

According to a recent study published in JAMA Oncology, it appears possible that, over long term, low-dose aspirin may cut ovarian cancer risk.

Low-Dose Aspirin May Cut Ovarian Cancer Risk

Aspirin, a nonsteroidal anti-inflammatory drug, can help with many health problems. It can reduce fever, ease pain, and even prevent a heart attack or stroke. For some time now researchers have looked into the connection between aspirin and cancer prevention.

Pre-existing evidence suggests that chronic or persistent inflammation plays a role in the development of cancer and other diseases. And it is believed that aspirin and other non-steroidal anti-inflammatory drugs may help to lower their risk by reducing inflammation.

Now, according to a recent study published in JAMA Oncology, it appears possible that, over long term, low-dose aspirin may cut ovarian cancer risk.  

A weapon against ovarian cancer

For this study, researchers from Harvard Chan School, along with fellow colleagues from Brigham and Women’s Hospital in Boston and Moffitt Cancer Center in Tampa, analyzed data gathered from 205, 498 American women. All of the women were part of the Nurses’ Health Study and Nurses’ Health Study II – two continuing studies that use questionnaires to monitor disease and health behavior in women. And of those women involved in the study, 1,054 developed ovarian cancer.

The researchers looked into the women’s use of aspirin, low-dose aspirin, non-aspirin NSAIDs, and acetaminophen, as well as considered relevant information such as duration of use, timing, and frequency. They found that the women who reported recent, regular use of low-dose aspirin (100 milligrams or less) had a 23% lower risk of developing ovarian cancer, as opposed to the women who did not take aspirin on a regular basis. They also found that use of low-dose aspirin was associated with a lower risk of ovarian cancer, while use of standard-dose aspirin (325 milligrams) was not.

However, the researchers noted that a potential limitation was that the result was found only in women who had been taking low-dose aspirin for less than a year. Moreover, the risk did not fall the longer women took low-dose aspirin and the study did not prove that aspirin reduced cancer risk, just that there was an association.

Conversely, it was found that taking 10 or more tablets per week of non-aspirin NSAIDs, such as naproxen and ibuprofen, for multiple years may be associated with an increased risk of ovarian cancer. However, when NSAIDs were taken less than two days a week for five years or longer, they were not associated with an increased risk of ovarian cancer. “What really differentiated this study from prior work was that we were able to analyze low-dose aspirin separately from standard-dose aspirin. Our findings emphasize that research on aspirin use and cancer risk must consider aspirin dose. Our results also highlight the need for ongoing conversations between patients and their doctors on the risks and benefits of taking low-dose aspirin” said Mollie Barnard, lead author of the study and postdoctoral fellow at the University of Utah’s Huntsman Cancer Institute.

Weighing the evidence

According to the researchers, their findings indicate that recommendations made by the U.S. Preventive Services Task Force in the year 2016 advising older adults with an elevated risk of cardiovascular disease to take low-dose aspirin are not likely to increase the risk of ovarian cancer. “Our findings expand on two consortium studies showing that daily aspirin is related to lower ovarian cancer risk. Many people take a low-dose aspirin daily for heart disease prevention” said Shelley Tworoger, senior author of the study and associate center director of population science at the Moffitt Cancer Center.

Other researchers also believe that further research is necessary in order to verify the results and to determine which women can benefit most from taking low-dose aspirin to cut down their risk of ovarian cancer. “The results are slightly puzzling in relation to aspirin, with low doses showing a decreased risk and higher doses showing an increased risk. This could be an indication that unmeasured factors are an explanation for the findings” said Stephen Evans, a professor of pharmacoepidemiology at the London School of Hygiene & Tropical Medicine.

Eric J. Jacobs, a cancer epidemiologist and strategic director of pharmacoepidemiology at the American Cancer Society, said that best case scenario, the results suggest that aspirin only slightly reduces the risk of ovarian cancer. “There is still too little evidence to conclude that aspirin use helps lower risk of liver or ovarian cancer, and people should not take aspirin in the hopes of preventing these cancers” he added.

Reducing the burden

In the United States, millions of adults take aspirin to reduce their risk of heart attack or stroke. However, studies over the last 20 years have suggested that regular use of aspirin may have another possible benefit: cutting down the risk of developing or dying from some types of cancer – including ovarian cancer.

Unfortunately, ovarian cancer remains the most fatal gynecological cancer due to lack of early detection strategies. For this reason, there is vast potential for improvement in both screening and treatment options for this disease. While it may be too soon to tell for sure that aspirin reduces the burden of ovarian cancer, researchers continue in their efforts to identify what it may be able to do. The next step would be to determine if any anti-inflammatory medications can be used in combination with standard therapies to improve survival rates among women diagnosed with ovarian cancer, as well as to determine which specific doses are the most appropriate. “Especially in an environment where we know there can be real harms of long-term aspirin use, we have to have the best possible information to make sure we know its benefits definitely outweigh its harms” said Dr. Kirsten Bibbins-Domingo, general internist and attending physician at Zuckerberg San Francisco General Hospital.

The bottom line when it comes to taking aspirin is that neither the American Cancer Society, nor any other healthcare organization, recommends solely relying on the daily use of this medication to help with cancer outcomes. Each individual should talk with their healthcare provider, as use of aspirin greatly depends on one’s personal medical history and any current medications being used. These factors should be considered when weighing the benefits and risks associated with use of aspirin, seeing as how it may not be the right fit for everyone.  


  1. https://www.webmd.com/ovarian-cancer/news/20181004/low-dose-aspirin-may-cut-ovarian-cancer-risk
  2. https://www.hsph.harvard.edu/news/press-releases/aspirin-lower-ovarian-cancer-risk/
  3. https://edition.cnn.com/2018/10/04/health/aspirin-ovarian-cancer-study/index.html
  4. https://www.cancer.gov/about-cancer/causes-prevention/research/aspirin-cancer-risk
  5. https://www.cancer.org/latest-news/aspirin-and-cancer-prevention-what-the-research-really-shows.html