Isolated oligohydramnios at term: is induction indicated?

low-risk pregnancy include evaluation of decreased fetal movement, spontaneous variable decelerations during monitoring to evaluate for labor, or an ultrasound evaluation for fundal height measurements discordant with gestational age. How should “isolated” oligohydramnios—an AFI <5 cm—be interpreted, and should immediate induction be recommended for such patients? Oligohydramnios occurs in about 1% to 5% of pregnancies at term. Because adverse outcomes occur in high-risk pregnancies complicated by low amniotic fluid volume, oligohydramnios commonly prompts labor induction. At one university center, oligohydramnios is now the leading indication for labor induction. Many centers may even induce labor when the AFI is between 5 cm and 8 cm, the so-called borderline AFI. Labor induction increases the use of cesarean delivery, particularly for the primiparous woman with an unripe cervix. Recent studies questioning the safety of labor induction in women who have had a cesarean may increase the number of elective repeat cesarean procedures when delivery is believed indicated for oligohydramnios. (See Underlying causes of oligohydramnios.)