Induction of labor by intracervical prostaglandin gel and oxytocin infusion in primigravid women with unfavorable cervix. Role of the cervix in the induction of labor. Induction of labour: a randomised clinical trial of amniotomy versus amniotomy with oxytocin infusion. Induction of labour: a comparison of two methods with particular concern to patient acceptability. Comparison of intravenous oxytocin and prostaglandin E2 for induction of labour using automatic and non-automatic infusion techniques. Extra-amniotic saline infusion versus extra-amniotic prostaglandin F2alpha for cervical ripening and induction of labor. Extraamniotic saline infusion is promising in preparing the cervix for induction of labor.
The rate of Cesarean Section for failed induction of labor and maternal and fetal compilations are high when labor is induced in a nulliparas women with an unripe cervix by amniotomy and oxytocin infusion. Prostaglandins (PG) in different forms have been used for ripening the cervix with an aim of reducing these problems. A prospective randomized trial was performed on one hundred primigravid women between 37 and 42 weeks of gestation with singleton pregnancy, cephalic presentation and unfavorable cervix (Modified Bishop Score < or = 5) in the department of Obstetrics & Gynaecology of Institute of Postgraduate Medicine & Research from 1st May 1996 to 30th April 1997. In this study the efficiency of prostaglandin E2 intracervical (PGE2 IC) gel in induction of labor in a group of primigravid women with unripe cervix was assessed and compared with another group with similar characteristics using oxytocin infusion and artificial rupture of membrane (ARM). The Modified Bishop Score (MBS), interval between IOL and onset of labor and the duration of labor after insertion of PGE2 gel was significantly different from those of oxytocin infusion group. But the Apgar Score at 1 & 5 min had shown no statistically significant difference. Any significant difference could also not be detected in the mode of delivery between the two induction group. The proportion of emergency Cesarean Section (CS) was high in the oxytocin infusion group than that of in the prostaglandin group. There was also no significant difference regarding the acceptability of both the induction methods. A study on induction of labor was carried out to test the hypothesis that changing the cervix will enhance the effectiveness of induction of labor. Fifty pregnant women near term with Bishop scores of 4 or less were divided into 5 study groups, in which a 12-hour preparation phase procedure was carried out to produce cervical or myometrial changes. All women had continuous measurement of uterine activity by an extraovular catheter. The patients were divided into 1) control subjects, and into groups treated with 2) laminaria, 3) Foley catheter, 4) amniotomy, and 5) oxytocin infusion. These preparation techniques were used for 12 hours, after which rupture of membranes was carried out in all cases. Although all procedures significantly changed the cervix, none but oxytocin affected the induction-to-delivery interval. The authors concluded that when a study design rigidly controls for cervical Bishop score, timing of rupture of membranes, and oxytocin infusion rates, the cervical preparation alone will not enhance inducibility. To compare two methods of induction of labour-amniotomy with oxytocin infusion versus amniotomy alone.
                Prospective randomised clinical trial.
                The department of obstetrics in a Swedish central hospital.
                One hundred and ninety-six pregnant women with indication for induction of labour at term and a favourable cervix (modified Bishop score > or = 6).
                The women were randomised to amniotomy followed by oxytocin infusion after 1 h (group A, n = 98) or amniotomy alone (group B, n = 98). If labour had not ensued on the following morning, after approximately 24 h, the women in group B were given an oxytocin infusion.
                Induction-delivery interval, duration of labour, time spent in delivery ward, oxytocin use, maternal and neonatal clinical outcome.
                Amniotomy combined with early oxytocin infusion resulted in shorter induction-delivery interval (median 6.0 h; 95% confidence interval (CI) 5.0 to 6.5 h) than amniotomy alone (median 9.0 h; 95% CI 7.5 to 10.0 h). This was due to a shorter latent period in the former group (median 2.3 h; 95% CI 2.0 to 3.0 h) compared to the latter (median 4.3 h; 95% CI 3.0 to 5.5 h). The duration of labour stages 1 and 2 were similar in both groups. The time spent in the delivery ward was slightly reduced for women managed by amniotomy alone (median 5.0 h; 95% CI 4.5 to 6.0 h) compared with those managed by the combination of amniotomy and oxytocin infusion (median 6.0 h; 95% CI 5.0 to 6.5 h). Eighty-seven percent in group A and 32% in group B were given oxytocin, and the total oxytocin infusion time was nearly five times longer in group A. No other important effect on maternal or fetal outcomes was demonstrated.
                With regard to safety the results do not warrant recommending either type of labour induction. The minor differences observed between the induction groups justify an individual management policy, with attention paid to both the indication for induction of labour and the woman's choice. Induction of labour is a common obstetric intervention. When the cervix is unfavourable ripening agents are used, commonly prostaglandin E2. There are several methods of administration of prostaglandin E2 and little comparative work has been performed as to their acceptability by patients. Patients undergoing induction of labour by prostaglandin E2 were randomised to receive either intravaginal gel or an intravaginal slow-release pessary. Patient satisfaction with the method received was then assessed. Sixty-nine patients were randomised, 34 to receive gel and 35 to receive a pessary. Median scores for satisfaction of the induction process were the same for both methods; however, satisfaction with the labour was increased with those who had been randomised to the pessary group (median pessary=5, gel=4). There may be a marginal improvement in patient satisfaction when a slow-release intravaginal prostaglandin E2 pessary is used for the induction of labour. A double blind trial of prostaglandin E2 and oxytocin given by intravenous infusion after amniotomy for induction of labour in 100 primigravidae with unfavourable induction features is reported. No clear-cut advantage of either drug emerged although PGE2 was perhaps superior when the cervix was highly unfavourable. Prostaglandin E2 appeared to produce less deleterious effects on the fetus but was associated with a higher incidence of maternal side effects. The automatic Cardiff Infusion apparatus was found to be a safe means of PGE2 infusion and to have advantages over the use of non-automatic techniques both for PGE2 and for oxytocin infusion. To compare the effectiveness of extra-amniotic saline infusion versus extra-amniotic prostaglandin F2alpha for cervical ripening, induction of labor and achievement of vaginal delivery in patients with unfavorable cervices.
                A randomized trial of extra-amniotic saline infusion versus extra-amniotic prostaglandin F2alpha performed at Harare Central Hospital Maternity Unit, Zimbabwe. One hundred and sixty-four patients were recruited from those referred to Harare Central Hospital Maternity Unit who required induction of labor for either maternal or fetal indications.
                162 patients (extra-amniotic PgF2alpha group, N = 81; extra-amniotic saline infusion group, N = 81) had complete information. Two patients (one from each group) were lost to follow up. The demographic characteristics of the patients and the indications for induction were not statistically different. There was a marginally statistically significant difference in the change of Bishop Score in favor of the extra-amniotic saline infusion (4.0, S.D. = 1.4) as compared to (4.5, S.D. = 1.5) for extra-amniotic PgF2alpha (P value = 0.047). All other parameters showed no statistically significant differences. Maternal and fetal complications were minimal and not significantly different. Extra-amniotic saline infusion was however almost six times cheaper than PgF2alpha.
                Extra-amniotic saline infusion is as effective as PgF2alpha, safe, but much cheaper than PgF2alpha and should be seriously considered as a method of first choice in resource-poor settings. The application of local prostaglandins before induction of labor in women with an unripe cervix is standard procedure in Sweden. Side effects include uterine hypertonus and occasionally fetal heart rate abnormalities. Failed ripening is reported in up to 25% of cases. A previous report of ripening of the cervix by use of extraamniotic physiologic saline infusion through a Foley catheter applied in the cervix claimed results superior to topical prostaglandins.
                To conduct a prospective randomized trial of extraamniotic saline infusion and intracervical application of dinoprost 0.5 mg on cervical ripening and outcome of labor.
                Eighty-five term singleton pregnant women with unripe cervices where induction of labor was indicated were randomized to prostaglandin or saline infusion after obtaining informed consent. Outcome variables were improvement of cervical score, induction delivery time and mode of delivery.
                The 42 women in the saline infusion group obtained significantly (p < or = 0.001) higher cervical scores and shorter induction delivery intervals (p < or = 0.005) than the 43 women in the prostaglandin group. Cases of unripe cervix after 24 hours were significantly (p < or = 0.01) fewer in the saline group. There were more Cesarean sections in the saline group, but this difference was not significant. Saline infusion did not induce uterine activity and oxytocin was given in every case after the expulsion of the catheter.
                In this study extraamniotic saline infusion was a more efficacious method for ripening of the cervix than intracervical prostaglandin. The absence of early painful contractions is an advantage, but effective stimulation of labor is required to effect delivery after maturation of the cervix.
NO donors do not appear currently to be a useful tool in the process of induction of labour. More studies are required to examine how NO donors may work alongside established induction of labour protocols, especially those based in outpatient settings.