High prevalence of irritable bowel syndrome in women with chronic pelvic pain and discerning features relevant to deep endometriosis

• There is a high prevalence of irritable bowel syndrome (IBS), affecting 74.2% of women with chronic pelvic pain. • Women without endometriosis were significantly more likely to have IBS compared to those with endometriosis. • Patients with deep endometriosis were the least likely to meet the diagnostic criteria for IBS. • All women with chronic pelvic pain should be assessed for bowel symptoms, and IBS management should be considered where appropriate. Endometriosis is a chronic inflammatory condition associated with chronic pelvic pain (CPP), dysmenorrhea and bowel-related symptoms. Significant overlap exists between endometriosis and other benign abdominal pathologies, including irritable bowel syndrome (IBS). We aimed to identify the prevalence of IBS-related symptoms in a group of women undergoing either diagnostic or therapeutic surgical interventions for CPP. This ethically approved (IRAS 294803) prospective case-control study was undertaken between 8 th November 2021 and 22 nd February 2023. Premenopausal women presenting to the Liverpool Women's Hospital for surgical investigation and management of CPP completed an electronic questionnaire containing questions pertinent to the Rome IV diagnostic criteria for IBS and the validated British Society for Gynaecological Endoscopy (BSGE) endometriosis and pelvic pain questionnaire. Patients were grouped according to surgical findings: control (no endometriosis) (n = 49), superficial endometriosis (SE) ( n = 21), or deep endometriosis (DE) ( n = 19). Sixty-six (74.2%) women included in this study had a concurrent diagnosis of IBS. The prevalence of IBS was significantly higher in patients without surgical evidence of endometriosis (83.7% vs. 62.5%, p = 0.02). When considering endometriosis subtypes, patients with DE were less likely to meet the diagnostic criteria for IBS than those with SE and no endometriosis (57.9% vs. 66.7% vs. 83.7%, p = 0.062). Patients presenting with CPP, regardless of the underlying diagnosis of endometriosis, have a high prevalence of concomitant IBS. Clinicians should discuss bowel symptoms with all CPP patients and consider commencing concurrent IBS treatments as appropriate to improve patient symptoms.