Low amniotic fluid index at term as a predictor of adverse perinatal outcome

Aim: To determine whether an antepartum low amniotic fluid index (AFI) is a predictor of adverse perinatal outcome in normal pregnancy and to determine a threshold level of AFI that could predict an adverse outcome.

Methods: This was a prospective study conducted among 180 pregnant women at 37-40 weeks of gestation with no known obstetric or medical complications with an AFI ≤ 5th percentile. The results were statistically analyzed and compared.

Results: In the control group, the mean AFI was 10.14 cm and in the study group, it was 4.14 cm. 65 % patients in the study group and 24 % in the control group had a non-reactive non-stress Test. In the control group, 53 % of patients were induced for reasons other than oligohydramnios, while in the study group, 86 % of patients were induced for oligohydramnios. Among the control group, 33 % had a LSCS, while 67 % delivered vaginally; and in the study group, 34 % delivered vaginally and 66 % had a LSCS. In our study, a 5-min APGAR < 7 was seen in 34 % in the study group and 11 % in the control group. 33 % neonates in the control group and 64 % in the study group had birth weights <2.5 kg.

Conclusions: In the presence of oligohydramnios, perinatal morbidity and mortality are high. Determination of AFI is a valuable screening test for predicting fetal distress.