Polycystic ovary syndrome and risk of endometrial hyperplasia and endometrial cancer in women with abnormal uterine bleeding: A systematic review and meta-analysis.

Polycystic ovary syndrome (PCOS) is a prevalent endocrine disorder and a recognized risk factor for endometrial abnormalities. However, the relationship between PCOS and the development of endometrial hyperplasia (EH) and cancer (EC) in women experiencing abnormal uterine bleeding (AUB) remains inadequately defined. This meta-analysis aimed to assess the association between PCOS and the risk of EH/EC in this demographic. We conducted a systematic search of PubMed, Embase, and Web of Science from their inception until September 15, 2025. Observational studies comparing the risk of EH and/or EC in women with AUB and PCOS to those without PCOS were included. We utilized a random-effects model to pool data, estimating odds ratios (ORs) and 95% confidence intervals (CIs). Subgroup and sensitivity analyses were performed to evaluate the robustness of the findings and identify potential modifiers. A total of nine retrospective studies involving 6,064 women with AUB were included in this analysis. Among them, 462 (7.6%) had PCOS, while 704 (11.6%) were diagnosed with EH and/or EC. Our results indicated a significant association between PCOS and an increased risk of EH/EC (OR: 3.28, 95% CI: 2.54-4.25; I² = 0%, p < 0.001). This association remained consistent across sensitivity analyses and various subgroups defined by geographic region, menopausal status, analytic model, and study quality. Further analyses demonstrated heightened risks for EH (OR: 3.09, 95% CI: 2.49-3.82, p < 0.001) and EC (OR: 6.98, 95% CI: 4.68-10.40, p < 0.001) in women with PCOS. In conclusion, PCOS is associated with a significantly elevated risk of EH and EC in women with AUB. These findings underscore the necessity for enhanced endometrial surveillance in this high-risk population.