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, OR X3 vs 1 child ¼ 2.0, 95% confidence interval (CI) 0.7 -5.1), younger age at first birth (OR per 1-year decrease ¼ 1.2, 95% CI 0.99 -1.6), and older age at menarche (OR per 1-year increase ¼ 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.