Abstract: Objective To explore the association between sleep behavior and uterine leiomyomata(UL)risk in middle aged and elderly women.Methods A hospital-based retrospective study was conducted.Cases(n=385)were pathologically confirmed with UL and controls(n=385)were women with different diseases other than gynecologic diseases.All subjects were interviewed using a structured interviewer-administrated questionnaire and sleep behavior of the subjects were inquired with Pittsburgh Sleep Quality Index(PSQI)simutaneously.The odds ratio(OR) and the corre-sponding 95% confidence interval(CI)for UL and component scores of sleep behavior were estimated with multiple logistic regression model.Results The case group was significantly higher in grades of subjective sleep quality,habitual sleep efficiency,sleep disturbances,and overall PSQI scores than matched controls(P<0.05).Sleep quality,habitual sleep efficiency,sleep disturbances,and overall PSQI scores were associated with UL in univariate analysis.After adjustment for multiple potential confounders,compared with the controls,for the cases with scores≥2,sleep quality(OR=2.030,95% CI:1.261-3.181;P<0.001),habitual sleep efficiency(OR=2.437,95%CI:1.465-4.056;P<0.001),sleep disturbances(OR=1.564,95% CI:1.002-1.862;P=0.023),and overall PSQI scores were significantly related with the risk of UL.Compared with the women with the score＜5,the women with the scores of 5-10 and >10 had approximately two times risk of UL(OR=1.833,95%CI:1.308-2.497;P=0.002;OR=1.923,95%CI:1.515-2.687;P=0.014).UL risk may increase with the increment of component score(P<0.05).Conclusion Sleeping may be a risk factor of UL and premenopausal women should raise the consciousness of the sleep influence on UL and do regularly gynecological examinations to prevent the disease.