Women newly diagnosed with irritable bowel syndrome (IBS) face a heightened risk of ovarian cancer, particularly in the months following their diagnosis.
IBS Diagnosis May Signal Increased Ovarian Cancer Risk
LOS ANGELES, July 28, 2025—A new study suggests women diagnosed with irritable bowel syndrome (IBS) have a significantly higher risk of developing ovarian cancer within the first year after diagnosis. This elevated risk is most pronounced at three and six months post-IBS diagnosis but appears to diminish beyond eight months.
Ovarian cancer symptoms often mimic those of IBS, leading to potential misdiagnosis. Current IBS guidelines do not consistently recommend screening for ovarian cancer. Researchers investigated this link by conducting a retrospective cohort study using U.S. administrative claims data.
The study analyzed data from January 2017 to December 2020, identifying 9,804 women with a new IBS diagnosis and 79,804 women without IBS. Diagnostic codes were employed to pinpoint cases of both IBS and ovarian cancer.
Endometriosis Magnifies Risk
Women diagnosed with IBS exhibited a notable increase in ovarian cancer risk. Specifically, their hazard ratio was 1.71 at three months post-diagnosis (P = .02) and 1.43 at six months (P = .02). This elevated risk was not sustained beyond eight months.
The risk escalated dramatically for women with both IBS and endometriosis. At three months, their ovarian cancer risk was 4.20 times higher (P = .01), dropping slightly to 3.52 at six months (P = .01) and remaining elevated at 2.67 after one year (P = .04).
Age also played a role, but only in younger women. Increasing age was significantly associated with a higher incidence of ovarian cancer for women under 50, regardless of their IBS status. Their hazard ratio for this age group was 1.07 (P < .01).
Key finding: Women with IBS have a greater chance of developing ovarian cancer in the six months following their IBS diagnosis.
Personalized Care
“Identifying patient-specific risk factors, such as chronic pelvic pain or endometriosis, could help develop tailored risk profiles and improve the approach to personalized care in women with IBS-type symptoms,” the study authors stated.
The study was led by Andrea Shin from the Vatche and Tamar Manoukian Division of Digestive Diseases at the University of California, Los Angeles. It was published online in Alimentary Pharmacology & Therapeutics.
- Women with a new IBS diagnosis face a higher risk of ovarian cancer at three and six months post-diagnosis.
- This increased risk disappears after eight months for women with IBS alone.
- Women with both IBS and endometriosis have a significantly greater risk of ovarian cancer, persisting for over a year.
- For women under 50, increasing age is linked to a higher ovarian cancer incidence, irrespective of IBS status.
Limitations and Support
A limitation of the study is its reliance on diagnostic codes, which may not always accurately reflect a confirmed IBS diagnosis and could instead represent symptoms.
The research received support from the National Institutes of Health. Some authors reported consulting or advisory roles, research support from pharmaceutical and healthcare companies, and stock options.
