The Canadian Medical Associate Journal published a report (March 18, 2013) about a study that indicates an increased risk of gallbladder surgery because of gallstones among women taking estrogen via pill.
Interestingly, the risk decreases when the estrogen is taken via transdermal gel or patch. Dr. Bette Liu, on the medical faculty at the University of New South Wales in Sydney, Australia, weighed in on an accompanying editorial. Dr. Liu suggested that hormones prescribed to women during menopause be given in transdermal rather than oral form to minimized complicated gallstone disease.
Although the study shows a clear link between hormone replacement therapy (HRT) and gallstone disease, it did not establish a cause-and-effect relationship.