Prophylactic intrapartum amnioinfusion: a controlled retrospective study of 135 cases

To show that intrapartum prophylactic amnioinfusion (AI) in case of oligohydramnios or particulate meconium-stained amniotic fluid could be beneficial.

From the first March 1993 until the 30th June 1995, 4031 women were delivered at the University Hospital of Poitiers. Patients presenting with oligohydramnios (G1) (71 patients with an amniotic fluid index below 5 cm) or a particulate meconium-stained amniotic fluid (G2) (64 patients) were included. Each group was compared to an historical control group constituted retrospectively according to the following criteria: oligohydramnios (CG1), particulate meconium-stained amniotic fluid (CG2), age, parity, gestational age and duration of labor. Statistical analysis was performed using the Student's t-test and the Fisher's exact test when appropriate with a level of significance of P less than 0.05.

The mean infused volume was 893 ml in G1 and 734 ml in G2. A significant difference was found in terms of cesarean section between G1 and CG1 (11.3 vs. 24.5%; P < 0.05) and of assisted deliveries for fetal distress between G2 and CG2 (12.5 vs. 23.43%; P < 0.05). No other significant difference was found between the study groups and their control for all other studied criteria. When considering more specifically the presence of meconium below the vocal cords we also could not find any significant difference between G2 and CG2 (1.6 vs. 9.4%; P = 0.05). No neonatal or maternal adverse effect happened in this short study.

AI is easy to perform during labour in case of oligohydramnios or particulate meconium-stained amniotic fluid. In case of oligohydramnios, a decreased rate of cesarean sections has been observed in the infused group. Considering patients with particulate meconium-stained amniotic fluid, less interventions for fetal distress and neonates with meconium below the vocal cords has been found in the infused group. Further prospective evaluation is needed to confirm these results in case of particulate meconium-stained amniotic fluid and to compare the advantage of prophylactic versus therapeutic AI performed in case of oligohydramnios and abnormal fetal heart rate.