PURPOSE: To assess the frequency of fetal gallbladder visualization through gestation and to determine the prognostic importance of nonvisualization. MATERIALS AND METHODS: Demonstration of the gallbladder was prospectively attempted in 578 consecutive second- and third-trimester obstetric ultrasound examinations. Data regarding gallbladder visualization were stratified into subgroups on the basis of estimated gestational age. Postnatal follow-up was performed in 80 fetuses with nonvisualization of the gallbladder. RESULTS: The gallbladder was seen on 477 of 578 (82.5%) fetal sonograms. The likelihood of gallbladder visualization increased with advancing gestational age, reaching a plateau of approximately 95% between 24 and 32 weeks. After 32 weeks, the frequency of visualization declined. Seventy-five of the 80 fetuses with nonvisualized gallbladders who underwent follow-up had normal outcomes. Except for one fetus with trisomy 21, all fetuses with abnormalities had relatively minor, non-life threatening problems that did not involve the gallbladder or biliary tract. CONCLUSION: Most fetuses with nonvisualization of the gallbladder have normal outcomes. The rate of nonvisualization of the fetal gallbladder is sufficiently high to undermine the utility of gallbladder visualization as a screen for fetal abnormality.