Amnioinfusion in the management of oligohydramnios

Oligohydramnios, with its extremely varied aetiology, is associated with unfavourable perinatal outcome, especially if detected during the second trimester. Amnioinfusion has recently become widely used for the diagnostic, prophylactic and therapeutic management of oligohydramnios, although as yet no incontrovertible proof exists of its advantages over conservative treatments. This study analyses our preliminary experience regarding antepartum amnioinfusion, aimed at clarifying its diagnostic and therapeutic role and its relative harmlessness. The outcomes of 80 pregnancies with oligohydramnios were analysed, comparing the 35 amnioinfused cases with the 45 conservatively treated ones; the cases were classed as second or third trimester, according to when a reduction in amniotic fluid was diagnosed. In the amnioinfused group, latency was longer; this was only significant in the third trimester (a median 14 days vs. 5 days; p < 0.05), no difference occurring in the incidence of spontaneous abortion, intrauterine death or preterm delivery. Analysis of neonatal outcomes at the second trimester shows a lesser incidence of neonatal deaths (5% vs. 33%; p < 0.05). The number of neonates discharged after amnioinfusion at the II trimester (3 out of 4) constitutes 75% of live births, compared with only 25% (2 out of 8) among those not undergoing amnioinfusion in the same period. Cumulative analysis of neonatal complications in the two treatment groups revealed no significant differences; cases of serious neurological damage at the third trimester were more frequent in the non-amnioinfused group (7 out of 27 vs. 0 out of 15; p < 0.05). There were no differences between the two groups (amnioinfused and not) with regard to maternal parameters of phlogosis analysed (leukocytosis, hyperpyrexia, CRP C-reacting Protein). In conclusion, our experience shows that within the limits of the small number of samples here used, amnioinfusion, involving few maternal or fetal risks, is advantageous as to perinatal mortality and morbidity. We thus confirm it as one of the few available methods in the active management of pregnancies affected by second-term and incipient third-term oligohydramnios.