Ovarian cancer is a common cancer of the internal (female) reproductive system. It is the fifth leading cause of cancer death in people with ovaries.

Several studies have examined the role of pain medications on ovarian cancer risk, with mixed results. A trend throughout many studies indicates that low dose aspirin may reduce risk.

In this article, we’ll go over the research on aspirin and ovarian cancer. We’ll also discuss who should and shouldn’t take aspirin, and the risk factors for this disease.

Research on analgesic (pain medication) use and ovarian cancer risk goes back several decades and spans multiple countries. We reviewed several large, recent studies and found trends as well as mixed results.

Some studies focused specifically on epithelial ovarian cancer. Epithelial ovarian cancer originates in cells that cover the outer surface of the ovary. Most ovarian cancer tumors originate in this part of the ovary. These types of tumors are referred to as epithelial cell tumors.

Research summary

  • Low dose aspirin. Many studies indicate that using low dose aspirin significantly reduces ovarian cancer risk. The reason for this remains speculatory, although it’s likely due to reduced inflammation. It’s unclear whether or not long-term use has any benefit, as studies had mixed results.
  • Regular dose aspirin. Some studies found that regular dose aspirin reduced risk, but not to the same extent as low dose aspirin.
  • NSAIDs and acetaminophen. Results about NSAID use and ovarian cancer risk were mixed. Acetaminophen was not found to have any impact.
Was this helpful?

Of the studies we reviewed, these are the largest and most comprehensive. Some studies use gender-specific language. We have retained the original phrasing so as not to inadvertently skew results.

A 2014 review found that daily use of low dose aspirin — under 100 milligrams (mg) — could reduce ovarian cancer risk by 20 to 34 percent. The study also suggested that dosage and frequency affected how much a person’s risk was reduced. Researchers also looked into the effects of similar regimens:

  • Regular dose aspirin reduced risk to a lesser extent.
  • High dose nonaspirin NSAIDs (over 500 mg) reduced risk to a lesser extent.
  • Acetaminophen use had no effect.

A 2018 study found that women taking low dose aspirin on a regular basis had a 23 percent reduced risk of ovarian cancer compared to women not taking aspirin. Researchers followed more than 200,000 participants for either 26 or 34 years but did not observe a reduction in risk with long-term use (5 years or more) of low dose aspirin. They also found that women who took NSAIDs at a high dose long-term had an increased risk of ovarian cancer.

A nationwide, case-controlled study from Denmark found that using low dose aspirin reduced epithelial ovarian cancer risk. For this study, the researchers defined low dose aspirin as 75 to 150 mg. Unlike the Harvard study, researchers found that continuous long-term use further decreased risk.

Before you start using aspirin, either low dose or regular dose, talk with your doctor. Aspirin is not the right choice for everyone.

Doctors don’t recommend aspirin for people with these conditions:

Risks of using aspirin include:

  • irritation to the stomach lining
  • gastrointestinal upset
  • ulcers
  • bleeding
  • easy bruising

Doctors often prescribe low dose aspirin to reduce the risk of heart attack and stroke. Aspirin’s role in cancer prevention is not conclusive, but it is compelling.

Some data indicate that low dose aspirin may be beneficial for reducing colorectal cancer and gastrointestinal cancer risk.

But there’s also research indicating that taking low dose aspirin may increase the risk of dying from advanced cancer in people ages 70 and older.

Talk with your doctor before you begin any sort of aspirin regimen for cancer prevention.

Most of the risk factors for ovarian cancer are beyond your control. They include:

  • being age 45 or older
  • family history of ovarian or breast cancer
  • personal history of breast cancer
  • testing positive for BRCA1 or BRCA2
  • having Lynch syndrome
  • having endometriosis
  • menstruating early or entering menopause late

Ovarian cancer is a common cancer of the internal (female) reproductive system. Several studies have analyzed the effects of taking low dose aspirin on ovarian cancer risk.

Some studies found that low dose aspirin can significantly reduce the risk of ovarian cancer. Studies found high dose aspirin to reduce risk slightly.

Aspirin is not the right choice for everyone. Before you begin taking aspirin as a cancer preventive, talk with a healthcare professional.