Randomized trial of administration of prostaglandin E2 gel for induction of labor in the morning or the evening. Double-blind trial of prostaglandin F2alpha and oxytocin in the induction of labour. [Comparison between prostaglandin E2 gel and oxytocin in medically indicated labor induction].
To compare the outcome of induction of labor and patient's preferences using a protocol with the first dose of prostaglandin E2 endocervical gel in the evening versus a protocol with the first dose in the morning.
                We performed a randomized trial comparing administration of prostaglandin E2 endocervical gel in the morning with administration of prostaglandin E2 gel in the evening, followed if necessary by a second dose being given after six hours if labor had not started or the cervix was still unripe. Formal induction of labor by amniotomy and oxytocin infusion was performed the morning after the initial prostaglandin E2 dose. Patients' preferences were assessed using a questionnaire that was completed after delivery.
                Tertiary care hospital in the Netherlands with 1,600 deliveries per year.
                One-hundred and twenty-six women with viable singleton pregnancies at term who had induction of labor with prostaglandins.
                Time of delivery (daytime, evening or night) and patient's satisfaction.
                Fifty-eight women were allocated for administration of gel in the morning, whereas 68 had their gel in the evening. Administration of gel in the evening did not significantly reduce delivery between 23.00 hours and 08.00 hours, although there was a reduction in delivery between 23.00 hours and 08.00 hours in nulliparae. None of the multiparous women delivered between 18.00 hours and 23.00 hours after induction of labor in the evening. The relative risk for delivery by vacuum or forceps was increased after allocation of gel in the evening (4.2; 95% confidence limits 1.4 to 13). Patients' preferences favored administration of gel in the morning.
                There was no benefit in starting induction of labor with prostaglandin E2 in the evening, compared with starting in the morning. In a random double-blind trial in 28 pregnant women at term, labour was induced with either prostaglandin F2alpha or oxytocin given by intravenous infusion. The results showed that prostaglandin F2alpha was as active as oxytocin and induction was successfully carried out in 24 patients; 3 patients had a caesarean section because of an obstructed labour and 1 patient on oxytocin did not have regular contractions after 10-hours' infusion although she delivered spontaneously 2 days later. No difference was found in the induction--delivery interval in the 8 patients in each group who had early amniotomy (first 90 minutes). No adverse effects were noted in either mother or the child. The authors recommend that to avoid side-effects the dosage of 20 mug prostaglandin F2alpha per minute should not be exceeded and that, although no cardiotocographic abnormalities were noted, this method of control should be used. The use of prostaglandins (PG) increasingly replaces the "classical" method of induction of labour by means of oxytocin and amniotomy, the last-named method being associated, especially in women with an unripe cervix, with side effects like prolonged labour and a higher rate of obstetric surgery. In this study the point of interest was whether prostaglandins offer any advantages over the classical method in respect of efficacy and maternal and foetal tolerance. 99 patients subdivided into primiparae and multiparae were randomly assigned to group A or B. In group A labour was induced with 1 mg resp. 2 mg PGE2 intravaginally at an interval of 6 hours. In group B the method of induction consisted of intravenous oxytocin and amniotomy. The success rate of induction was almost equal in both groups. However, in those patients where PGE2 induction did not succeed and who could not be delivered within 12 hours the cervical score was significantly improved in comparison to the oxytocin group. Based on the experience reported in the literature, one might speculate that an increased dosage could still improve the results of vaginally administered PGE2 gel.
Taking into account women's preferences that favoured administration of prostaglandins in the morning, we conclude that caregivers should preferably consider administering prostaglandins in the morning.
There is no strong evidence that induction of labour with intravenous oxytocin in the evening is more or less effective than induction in the morning. Consideration may be given to start induction of labour with oxytocin in the evening when indicated.