To evaluate the incidence and symptoms of and risk factors for biliary sludge and gallstones during pregnancy and to assess the natural history of these conditions in the first year after delivery. Cohort study. A total of 272 pregnant women recruited in the first trimester. Biliary sludge and gallstones were diagnosed using ultrasonography, both during pregnancy and after delivery. Predictors of the presence or disappearance of sludge and stones were examined. Overall, from the first trimester of pregnancy until the immediate postpartum period, 67 women were newly diagnosed with biliary sludge, and 6 women were newly diagnosed with gallstones. The respective incidence rates were 31% (95% Cl, 25% to 37%) and 2% (95% Cl, 0.2% to 4%). During pregnancy, 28% of women experienced biliary pain, which was associated only with presence of stones. After delivery, 92 women had sludge and 23 had stones. Sludge disappeared in 61% of these women (Cl, 50% to 73%) after a mean follow-up of 5 months, and stones disappeared in 28% of women (Cl, 10% to 46%) after 9.7 months of follow-up. Biliary sludge occurred frequently during pregnancy but was generally asymptomatic and often disappeared spontaneously after delivery. Gallstones were much less frequent and were more likely to be associated with biliary pain.

All 2583 residents of Rochester, Minnesota, who had gallstones initially diagnosed during the years 1950 to 1970 were followed for the development of gastrointestinal malignancies. Although 69 members of the cohort subsequently developed 72 gastrointestinal malignancies, this number of cases did not exceed the 76 cases expected (relative risk, 1.0). The risk for gallbladder cancer was increased threefold, but the increase was significant only in men (p = 0.05; 95% confidence interval, 1.0 to 30.0). The absolute incidence and the total number of men and women who developed gallbladder cancer was low (n = 5). The actual incidence of other gastrointestinal malignancies in our cohort with gallstones did not exceed the expected incidence in the general population of Rochester, Minnesota. Specifically, the risk for colon cancer was not increased, even after cholecystectomy. These data support an association between cholelithiasis and gallbladder cancer. We found, however, no association between cholelithiasis or cholecystectomy and any other gastrointestinal malignancy.