Prediction of successful labor induction by evaluation of maternal symptoms at an early stage of the misoprostol induction protocol

An audit of oral administration of Angusta® (misoprostol) 25 µg for induction of labor in 976 consecutive women with a singleton pregnancy in a university hospital in Denmark

INTRODUCTION

Induction of labor (IOL) is used to improve the outcome of pregnancy for mother and child. Since 2013, oral misoprostol has been used for IOL at Aarhus University Hospital, Denmark. The purpose of the present paper is to describe our experience of the use of a new, 25-µg misoprostol tablet commercially manufactured for the purpose of IOL regarding efficacy and outcome for mother and neonate in both an inpatient and an outpatient regimen.

MATERIAL AND METHODS

We performed an audit from 1 April 2016, including data on all IOL in women with singleton pregnancies until 1000 consecutive women were registered. Data from 976 consecutive women with gestational age ≥37⁺⁰  weeks induced in accordance with the "Aarhus protocol" were included in the present analyses. All inductions were by oral misoprostol. Outpatient induction is standard procedure in low-risk pregnancies, that is, pregnancies with a healthy mother and no signs of placental insufficiency. In the outpatient IOL, the first dose of misoprostol is administered after a normal cardiotocography registration at the hospital. Subsequent doses are taken at home according to a predefined regimen. Following delivery, data on baseline variables and outcome variables for the mother and neonate were retrieved from the medical records.

RESULTS

In 71.9% of cases, the women were induced in an outpatient regimen. Delivery within 24 hours was achieved in 38.8% of women (nulliparous 32.3%, multiparous 50.9%) and within 48 hours in 70.1% (nulliparous 66.2%, multiparous 77.2%). Hyperstimulation during induction occurred in 0.6%. The mode of delivery was spontaneous vaginal in 75.5% of cases. The cesarean section rate was 14.9% (nulliparous 20.7%, multiparous 4.1%). Apgar <7 at 5 minutes and pH <7.0 in the umbilical artery was seen in 0.9% and 0.7%, respectively.

CONCLUSIONS

Induction of labor by a commercially produced low-dose (25 µg) misoprostol tablet for oral induction according to the "Aarhus protocol" is feasible in an outpatient as well as an inpatient regimen. Delivery was achieved within 48 hours for 70.1% of women. Few adverse events were seen; however, the audit was underpowered for safety.