Nonvisualization of the fetal gallbladder in early pregnancy: Comparison with clinical outcome

PURPOSE: To prospectively assess the frequency of a nonvisualized fetal gallbladder in early pregnancy and to determine its prognostic value. MATERIALS AND METHODS: Fetal transvaginal ultrasonography (US) was performed in 29,749 consecutive pregnant women at 14-16 weeks gestation. A nonvisualized fetal gallbladder was defined if the gallbladder could not be depicted during two targeted examinations within I week. In such cases, women were offered an amniocentesis for fetal karyotype and hepatic enzyme analysis. Repeat transabdominal fetal US was performed at 22-26 weeks' gestation. If the gallbladder was still not depicted, US was performed postnatally. RESULTS: The gallbladder was not visualized in early pregnancy in 34 fetuses (0.1%; incidence of one in 875 pregnancies). Associated structural malformations were detected in 14 of 34 (41%) fetuses, five of which also had an abnormal karyotype. Pregnancy was terminated in nine of these 14 fetuses. In the remaining five patients who continued pregnancy, the gallbladder was detected later in pregnancy in four. However, only one infant was healthy. Nonvisualization of the gallbladder as an isolated finding was noted in 20 of 34 (59%) fetuses, all of which had a normal outcome. The gallbladder was detected later in pregnancy in 11 of these fetuses and after birth in two neonates, while no gallbladder was detected after delivery in five other neonates. Two patients were lost to follow-up. CONCLUSION: Nonvisualization of the fetal gallbladder in early pregnancy is uncommon but associated in many cases with other fetal anomalies. (C) RSNA, 2002.