Pulsation of blood flow in the umbilical vein during the second trimester of pregnancy correlated to fetal malformation and chromosomal abberation.

In the present study the flow profile of the umbilical vein between the 14th and 24th weeks of pregnancy was examined for the first time in connection with pathological pregnancies and chromosomal/fetal anomalies, and compared with the flow pattern of normal pregnancies. The aim of our study was to clarify whether at this early stage in gestation the diagnosis of the fetal condition should be extended to include the monitoring of the umbilical vein and to assess the possibility of making predictions about the further course of pregnancy. 50 pregnant patients without complications, 21 patients later developing pregnancy-induced hypertension/intrauterine growth retardation, 16 pregnancies with fetal anomalies, and 4 pregnancies with chromosomal aberrations were scanned with color Doppler sonography to determine the flow spectra of the umbilical vein in a free loop. Admission criteria were single-child pregnancies and precise knowledge of the duration of gestation. Pulsations of the venous blood flow, which are physiological during the first three months of pregnancy, cease in normal pregnancies from the beginning of the second trimester. In cases where pregnancy-induced hypertension/intrauterine growth retardation developed, 2 out of 21 patients showed pulsations. In the pregnancies in which fetal and/or chromosomal anomalies occurred, pulsations in the flow pattern of the umbilical vein were detected in 14 out of 20 cases. The pulsations of the venous blood flow, which are attributable to a late diastolic reflux component in the venous circulation, are common finding in fetal/chromosomal anomalies. In our opinion, the flow spectrum of the umbilical vein should therefore be incorporated in sonographic screenings, and if pulsations are detected, we advise careful sonographic abnormality diagnostics and an investigation of the karyotype.