Umbilical vein pulsations: pathophysiological aspects and fetal outcome

Continuous forward now to the fetal heart in the umbilical vein is a normal Doppler finding. Altered fetal hemodynamics can cause a pulsatile flow pat tern in the umbilical vein. Pulsations in the umbilical vein were diagnosed in 14 pregnancies complicated by fetal hydrops, cardiac malformations, arr hythmia or severe intrauterine growth retardation. To document the fetal ou tcome, the results were analysed retrospectively. Compared with a normal Doppler group (N = 56), a signif icantly higher rate of perinatal death (Alpha < 1%), (64% vs 1.75%) was diagnosed, when pulsat ions in the umbilical vein were present. The Apgar-score was significantly lower (4.5 vs 8.4) (p < 0.0002) in the group with pulsations in the umbilic al vein. There was no significant difference of pH between the newborns of the two groups. Eight fetuses developed hydrops. Thirteen fetuses had incre ased reverse flow in the inferior vena cava. The vena cava of the acardiac fetus could not be identified. The knowledge of the poor outcome and the pathophysiologic relationships of fetal hemodynamics may be useful in clinical management. Therefore Doppler examination of the umbilical vein should be performed in high-risk pregnan cies.