Borderline or Marginal Amniotic Fluid Index and Peripartum Outcomes

The predictive accuracy of a borderline amniotic fluid index (AFI) for an adverse pregnancy outcome is uncertain. Pregnancy outcomes of a borderline versus normal AFI suggest an increased risk of meconium‐stained fluid, intrauterine growth restriction, cesarean delivery for a nonreassuring fetal heart rate, low Apgar scores, and neonatal intensive care unit admission with borderline fluid. These results are inconclusive because of study design variations, the absence of receiver‐operating characteristic curves, our inability to calculate likelihood ratios, and a lack of randomized trials. There is currently insufficient evidence to recommend additional antenatal testing delivery based on a borderline AFI. Sonography could be considered for evaluating fetal growth until a definitive association or lack of an association between a borderline AFI and intrauterine growth restriction/small size for gestational age can be determined.