Relief of Presumed Compression in Oligohydramnios: Amnioinfusion Does Not Affect Umbilical Artery Doppler Waveforms

Abstract

The suggestion that amnioinfusion improves umbilical artery Doppler indices of downstream resistance in oligohydramnios by relieving cord compression was investigated by obtaining waveforms before and immediately after amnioinfusion in 16 pregnancies with severe oligohydramnios. There was no significant difference in the change in umbilical artery pulsatility index (PI) between 11 pregnancies in which amniotic fluid volume was restored (mean ΔPI = ––0.07, 95% confidence interval ––0.17 to +0.07), and 5 pregnancies in which immediate vaginal leakage of infused fluid prevented restitution of amniotic fluid volume. Fetal heart rate did not change significantly in either group. End-diastolic frequencies did not return with restitution of amniotic fluid volume in the 2 pregnancies in which they were absent before infusion (absent in 1, reverse in 1). This study suggests that restitution of amniotic fluid volume in human pregnancies complicated by severe oligohydramnios does not acutely alter the umbilical artery PI.

Transabdominal Amnioinfusion for the Management of Nonlaboring Postdates with Severe Oligohydramnios

“…Oligohydramnios is considered to be in itself a symptom of fetal compromise. Furthermore, it is thought that cord compres sion may contribute to peripartum asphyxia [8] , although the role of compression has been challenged on the basis of indirect evidence from mid-trimester umbilical Doppler studies [9] . Hence, the rate of cesarean delivery, either prophylactic or for fetal distress, is greatly increased.…”