[Varix of the extra-hepatic portion of the fetal intra-abdominal umbilical vein: pathogenesis, prenatal sonographic diagnosis, and perinatal outcome].

Aim. Aim of the study was to investigate pathogenesis, diagnosis, and prognosis of the fetal intra-abdominal umbilical vein varix (FIUVV). Methods. We reviewed all cases of FIUVV diagnosed in our hospital from August 1999 to December 2002. The umbilical vein was considered dilated when the measurement was above 2 standard deviation of the mean for gestational age. In all cases prenatal echocardiography and post-natal karyotype were performed. Our cases were also considered in the light of all the cases of FIUVV reported in literature. Results. FIUVV was diagnosed in 5 cases between 22 and 37 weeks' gestation, among an unselected population of pregnant woman. Karyotype was normal in all cases; an apparently isolated septal ventricular defect was present in one patient. No obstetrical complications due to the presence of FIUVV (i.e. thrombosis) were associated. Conclusion. In our case series no obstetrical complications, and only one mild fetal anomaly were present. In literature an high association has been reported between the presence of FIUVV and fetal anomalies and/or obstetrical complications. Fetal echocardiography and detailed US study of fetal anatomy is needed to exclude associated anomalies. Karyotype should be offered only when other fetal anomalies are present. In presence of FIUVV, a close fetal monitoring by serial color Doppler and ultrasonographic examinations should be performed.