Reverse flow in the human fetal descending aorta as a sign of severe fetal asphyxia preceding intrauterine death

Abstract

Flow velocity waveforms (FVW) in the descending part of the human fetal aorta were monitored in 35 cases of severe intrauterine growth retardation (IUGR) showing pathological intrauterine circulation (end-diastolic block). In 5 of the 35 fetuses, reversed aortic flow was observable during diastole and the simultaneously recorded CTG findings were pathological. All 5 fetuses having this circulatory sign died in utero within the next day. Controls were 260 healthy fetuses with normal growth curves; no end-diastolic block or reverse flow was found in this group. Diastolic reverse flow in the fetal descending aorta appears to reflect severely altered circulation preceding imminent fetal death.