Reproductive factors and risks of biliary tract cancers and stones: A population-based study in Shanghai, China

Abstract

Background:Parity has been linked to gallbladder cancer and gallstones, but the effects of other reproductive factors are less clear.Methods:We examined 361 incident biliary tract cancer cases, 647 biliary stone cases, and 586 healthy women in a population-based study in Shanghai.Results:The effects of parity (odds ratios, OR3 vs 1 child= 2.0, 95% confidence interval (CI) 0.7-5.1), younger age at first birth (OR per 1-year decrease= 1.2, 95% CI 0.99-1.6), and older age at menarche (OR per 1-year increase= 1.4, 95% CI 1.1-1.8) on gallbladder cancer risk were more pronounced among women with stones, but the interactions were not significant.Conclusion:Our results provide support for high parity, younger age at first birth, and late age at menarche in the development of gallbladder cancer, particularly among women with biliary stones. © 2010 Cancer Research UK All rights reserved.