Does an amniotic fluid index of ≤5 cm necessitate delivery in high-risk pregnancies? A case-control study, ,

Objective: This study was undertaken to determine whether women with high-risk pregnancies and an amniotic fluid index of ≤5 cm require labor induction to prevent adverse perinatal outcomes. Study Design: All women at high risk at ≥34 weeks’ gestation with an amniotic fluid index of ≤5 cm were admitted to the hospital for labor induction. Each woman was compared with the next patient at high risk seen with an amniotic fluid index of >5 cm and the same pregnancy complication. Case patients were also matched with control subjects for maternal race, age, parity, and gestational age. Results: Prospectively, 79 women at high risk with an amniotic fluid index of ≤5 cm were compared with 79 control subjects. There were no statistically significant differences between the 2 groups in the risks of thick meconium (P = .29), variable decelerations (moderate P = .27, severe P = .37), amnioinfusion (P = .37), cesarean delivery for fetal distress (P = .4), and umbilical artery pH <7.10 (P = .29). Conclusion: High-risk pregnancies with an amniotic fluid index of ≤5 cm appear to carry intrapartum complication rates similar to those of similar high-risk pregnancies with an amniotic fluid index of >5. (Am J Obstet Gynecol 1999;180:1354-9.)