Comparison of induced versus non-induced labor in post-term pregnancy. A randomized prospective study

Abstract

Objective: To determine the proper management of pregnancy in uncomplicated cases going beyond 42 weeks.

Design: Randomized controlled trial of induction of labor at or shortly after the 42-week limit, versus close monitoring without induction except when indicated for medical reasons.

Setting: Hospital's obstetrical department

Study population: 188 pregnant women, randomly allocated to two groups with 94 in each.

Interventions: Induction of labor by stripping of membranes and i.v. oxytocin infusion, with artificial rupture of membranes when the cervical opening was 3 cm or more in diameter. The control group was followed with clinical, biochemical and electronic tests, intervention being applied according to needs.

End points: Frequency and modes of operative delivery, maternal and perinatal morbidity and mortality.

Main results: The distribution of gestational age (in weeks) at birth was almost identical in the two groups, but there were more operative deliveries in the control group than in the induction group (64 versus 48, p less than 0.05). Maternal complications and perinatal morbidity rates were equally distributed between the groups. There was one perinatal death in the induction group and two deaths among the controls.

Conclusion: With due reservation for small numbers, routine induction after term may result in fewer operative deliveries. No other advantage has been demonstrated when compared with close monitoring and intervention when medically indicated.