The environmental risk factors related to uterine leiomyoma: An umbrella review

Uterine leiomyoma (UL) is the most common benign tumor of the reproductive period and become a major health problem. The present umbrella review assessed the environmental risk factors associated with UL based on meta-analyses studies.We searched three Major databases until February 2022. The meta-analyses that had focused on evaluating the environmental risk factors associated with the UL were included. The summary effect estimates, 95% CI, heterogeneity I², 95% prediction interval, small-study effects, excess significance biases, and sensitive analysis were applied. We used A Measurement Tool to Assess Systematic Reviews 2 (AMSTAR 2) for assessing the quality of the meta-analyses.The risk factor of chronic psychological stress (OR 1.24, 95% CI: 1.15, 1.34) and obesity (OR 1.19, 95% CI: 1.09, 1.29) was graded as suggestive evidence (class III). The current alcohol intake (OR 1.33, 95% CI: 1.01, 1.76) was graded as the risk factor with weak evidence (class IV). Current oral contraceptive (OCP) use (RR 0.43, 95% CI: 0.25, 0.73) (class IV), and former smokers (OR 0.93, 95% CI: 0.88, 0.99) (class IV) were as the protective factors.The current alcohol intake, chronic psychological stress, and obesity were risk factors for the UL, but current OCP use and former smokers were the protective factors.