Induction of labor in women with oligohydramnios.

Objective: To prospectively evaluate the outcome of labor induction in women with oligohydramnios at term.

Methods: This was a prospective case-control study which included 120 consecutive patients with Amniotic Fluid Index (AFI) < or =5 undergoing labor induction. One hundred and sixteen patients with normal amniotic fluid matched for gestational age (+/- 3 days) and Bishop-score served as controls. Inclusion criteria were: requirement of labor induction, singleton pregnancy, nulliparity, Bishop score <5, gestational age > or =266. Preinduction treatment included the use of up to 3 successive doses of dinoprostone intracervical gel (0.5 mg). Vaginal dinoprostone (2 mg) and/or oxytocin were then applied to induction labor, if necessary.

Results: The rate of cesarean section in AFI < or = 5 group (38.3%) was not significantly different to that in control group (34.2%). The interval from induction to vaginal delivery was not significantly different for AFI < or =5 group (1499 +/- 895 min.) and control group (1398 +/- 852 min.). The changes in Bishop score evaluated at 6th and 12th hour after dinoprostone were not significantly different in control and AFI< or =5 group. More women in the latter group (11.7% vs 3.3%, Chi Square:4.86, p = 0.027) required the use of drugs in order to manage tachysystole/hyperstimulation allowing a OR = 3.83 (95%C.I. = 1.13-14.27). The length of stay at hospital was 4.2 +/- 1.8 days for AFI < or =5 group and 4.3 +/- 1.3 for control group.

Conclusions: Oligohydranmios at term did not influence the outcome of induction of labour in nulliparous women with unfavorable cervix.