Oral contraceptive use and benign gallbladder disease; revisited

An analysis is described of 482 women with benign gallbladder disease (surgically confirmed in 407) identified in the Oxford Family Planning Association contraceptive study. There was no significant overall association between oral contraceptive use and gallbladder disease (relative risk ever use to never use 1.1, 95% confidence interval 0.9 to 1.3). Likewise, duration of oral contraceptive use had no significant effect (relative risk 97 or more months use to never use 1.1, 95% confidence interval 0.8 to 1.5). There was no indication of any interaction between oral contraceptive use and body mass index or oral contraceptive use and age in the production of disease. It is concluded that it is unlikely that oral contraceptives are of either clinical or public health significance in relation to the occurrence of gallbladder disease.