Management of premature rupture of the membranes after 34 weeks' gestation -- early versus delayed induction of labour

Abstract

Objective: To determine the optimal way to manage patients with premature rupture membranes after 34 weeks' gestation.

Design: A prospective, randomised controlled trial comparing immediate induction and delayed induction after 24 - 48 hours.

Setting: Tygerberg Hospital, Cape Town.

Participants: Seventy consecutive patients with premature rupture of the membranes who presented at Tygerberg Hospital between July and October 1991.

Main outcome measures: The two groups were compared with regard to infectious morbidity and antibiotic requirement in the mothers and babies, days spent in hospital, caesarean section rates, duration of labour and analgesic requirements.

Results: There was no difference between the two groups in terms of infectious morbidity in either the mothers or the babies, the duration of labour or the caesarean section rates. Nine patients (26%) in the delayed induction group required analgesic treatment during labour versus 18 patients (52%) in the group that was induced immediately (P = 0.049; odds ratio = 0.327; 95% confidence limits = 0.014 - 0.0998). In the delayed induction group, 74% of the patients went into spontaneous labour during the conservative management period. Patients in the active group (immediate induction) had a statistically significant better chance of being discharged within 48 hours of admission (P = 0.028; odds ratio = 3.34; 95% confidence limits = 1.12 -10.73).

Conclusions: The management of patients with premature rupture of the membranes afer 34 weeks should be decided upon according to the level of antepartum and neonatal care which is available at the particular unit. Where there is adequate neonatal support and pressure on bed occupancy, immediate induction of labour should be considered, while peripheral units should consider conservative management before referral of patients.