Post-cesarean versus primary bladder endometriosis and coexistent pelvic endometriosis: a systematic review

Objective: To investigate the prevalence of coexisting pelvic lesions in post-cesarean bladder endometriosis (BE) and primary BE. If women with post-cesarean BE exhibit a lower prevalence of coexistent endometriosis, it could be hypothesized that peritoneal damage of the vesicouterine fold, coupled with surgical dissemination of decidual fragments may be sufficient per se for lesion development. Data sources: Systematic search conducted in PubMed, Embase, and Scopus up to March 20th, 2025. Methods of study selection: Eligibility was defined using the PICOS framework: women with post-cesarean BE (Population); full pelvic assessment with surgical or imaging-based confirmation of endometriosis (Intervention); women with primary BE and no prior cesarean section (CS) (Comparator); presence of endometriosis beyond the bladder (Outcome); and case reports or series providing sufficient clinical/surgical details (Study type). Studies were evaluated using the Joanna Briggs Institute Critical Appraisal Checklists. The review followed PRISMA 2020 guidelines. No formal analysis was performed due to the descriptive nature of the data, but crude proportions were compared using Fisher's exact test. Tabulation, integration, and results: Of 7,378 records identified, 4,499 were screened and 374 full texts assessed. Eighty-one studies were included, accounting for 117 women with BE (26 post-cesarean, 91 primary). Coexistent pelvic endometriosis was significantly less frequent in post-cesarean BE (19.2%) than primary BE (79.1%) (p<0.0001). The odds of concomitant pelvic endometriosis were approximately 16 times lower in post-cesarean BE compared to primary BE (OR 0.06; 95% Confidence Interval, 0.02-0.20). In the limited number of post-cesarean cases with coexistent pelvic endometriosis, lesions were restricted to few 2021 #Enzian compartments. Conclusion: Peritoneal injury followed by iatrogenic dissemination of endometrial fragments during CS may be sufficient per se to cause BE, regardless of individual predisposition. Therefore, adopting surgical techniques that potentially reduce the risk of this long-term post-cesarean complication should be recommended.