Labour induction is frequently indicated in women with an unfavourable cervix. Oxytocin and prostaglandins are the most common drugs used for labour induction. Induction of labour with prostaglandins offers the advantage of promoting both cervical ripening and myometrial contractility. The purpose of the study was to evaluate the safety and efficacy intravaginal administration prostaglandin E1 methyl analogue, misoprostol in cervical ripening and induction of labour in term pregnancy and in women with unfavourable cervix (Bishop score < = 4). The approval for this study was given by the Board of Medical Ethics, University Medical School of Lublin in Poland.
Materials and methods: 64 women with indication for termination of pregnancy received either misoprostol (Cytotec-Searle) vaginally (group M, n = 30) or intravenous drip infusion of oxytocin(group Ox, n = 34). We evaluated profile of the studied women (gravidity, weight, height, maternal age, gestational age), effectiveness and safety of the misoprostol and need for oxytocin administration in group M, start of induction-to-active labour interval (contractions), start of induction-to-vaginal delivery interval, hyperstimulation syndrome, delivery within 24 hours of drug application and caesarean section rate. Before starting labour induction a Bishop score was obtained. Statistical analysis was performed. Baseline and outcome variables were tested with student's t-test and c2 analysis. We needed p < 0.05 for statistical significance.
Results: There were no differences in the patient profiles (gravidity, weight, height, maternal age, gestational age) between groups except the score of cervical ripening. The Bishop score before induction was lower in group M. The interval between the initiation of induction to active labour was shorter in the misoprostol group (334.23 +/- 126.35 versus 610.00 +/- 352.14 minutes). The mean time between the initiation of induction to delivery was shorter in group M (707.69 +/- 341.15 +/- versus 1025.77 +/- 369.16 minutes). These differences were statistically significant. 28 (93.33%) patients in the misoprostol group delivered within 24 hours compared with 24 (70.59%) women in the oxytocin group. 8 patients in the misoprostol group and 8 patient in the oxytocin group had caesarean section. Labor induction was successful in 30 (100%) women in the misoprostol group compared with 24 (70.59%) patients in the group Ox.
Conclusions: Intravaginal misoprostol is an effective, easy to use and cheap drug for the induction of labour, especially for cervical ripening in women with unfavourable cervix (Bishop score < = 4).