A randomized clinical trial of the intrapartum assessment of amniotic fluid volume: amniotic fluid index versus the single deepest pocket technique.

OBJECTIVE: The purpose of this study was to determine whether an intrapartum assessment of amniotic fluid identifies a pregnancy that is at risk for an adverse outcome.

STUDY DESIGN: Parturients who were admitted for delivery were assigned randomly to have the amniotic fluid assessed either by amniotic fluid index or by the presence of a 2 x 1 pocket.

RESULTS: The amniotic fluid index was obtained in 499 pregnancies, and the 2 x 1 technique was performed in 501. Oligohydramnios was diagnosed in 25% of amniotic fluid index pregnancies versus 8% with the use of the 2 x 1 pocket technique (P <.001). Both techniques failed to identify patients who underwent an amnioinfusion for fetal distress (P=.864) or who experienced variable (P=.208) or late decelerations (P=.210) that influenced delivery, fetal distress in labor (P=.220), caesarean delivery for fetal distress (P=.133), and admission to neonatal intensive care unit (P=.686).

CONCLUSION: Neither the amniotic fluid index nor the 2 x 1 pocket technique that was undertaken as a fetal admission test identifies a pregnancy that is at risk for an adverse outcome.