Relationship Between Female Hormonal and Menstrual Factors and Pancreatic Cancer: A Meta-Analysis of Observational Studies

The objective of this study was to assess the relationship between female hormone and menstrual factors and pancreatic cancer (PC) through a meta-analysis of observational studies. We undertook a systematic literature search up to July 10, 2014 in PubMed and EMBASE databases. Combined relative risks (RRs) were estimated by random-effects models. Subgroup analysis was performed by study design, source of control, and geographic regions. Sensitivity analyses and publication bias were utilized to evaluate the robustness of our results. A total of 27 case–control and cohort studies were retrieved for this meta-analysis. No significant associations were observed between the risk of PC and age at menarche (RR = 0.94, 95% confidence interval [CI] 0.83–1.07), age at menopause (RR = 0.98, 95% CI 0.85–1.13), hysterectomy (RR = 0.97, 95% CI 0.84–1.11), oophorectomy (RR = 1.02, 95% CI 0.82–1.26), hormone replacement therapy (RR = 0.97, 95% CI 0.87–1.08), and oral contraceptives (RR = 1.09, 95% CI 0.96–1.23). This meta-analysis of observational studies does not support the hypothesis that exogenous hormone use and menstrual factors are associated with PC.