DESIGN: randomised controlled trial of nulliparous women with spontaneous labour at term.
SETTING: labour suite of a university teaching hospital in Kuala Lumpur, Malaysia.
PARTICIPANTS: 240 women were included (120 randomised into two arms).
INTERVENTIONS: the randomisation sequence was generated using a computer randomisation program in two blocks: oxytocin infused early following amniotomy; and oxytocin infused 2 h after amniotomy.
MEASUREMENTS AND FINDINGS: labour duration, mode of delivery, oxytocin dosage used, uterine hyperstimulation, postpartum haemorrhage, Apgar score and admission to the neonatal intensive care unit were recorded. No differences in vaginal delivery rate (62.9% vs 70.9%; p = 0.248) and second-stage labour were found between the early and delayed oxytocin infusion groups (21.2 ± 18.3 min vs 25.5 ± 19.9 min; p = 0.220). The mean interval from amniotomy to vaginal delivery was significantly shorter for the early group (5.8 ± 1.7 h vs 7.0 ± 1.9 h; p = 0.001), and more women in the early group delivered during/before the planned review at 4 h after amniotomy (53.6% vs 10.6%; p<0.001). Maximum oxytocin usage was lower in the early group (5.6 ± 4.4 mL/hour vs 6.8 ± 5.3 mL/hour; p = 0.104).
KEY CONCLUSIONS: early oxytocin augmentation following amniotomy could be employed in low-risk primigravida, given that it is associated with a shorter labour duration without jeopardising maternal or neonatal outcomes.
IMPLICATIONS FOR PRACTICE: low-risk primigravida benefit from early oxytocin infusion following amniotomy, and this can be offered as an additional practice in labour room care.
METHODS: This non-blinded, randomized clinical trial included 228 pregnant women at term with obstetric or medical indications for induction of labour. Women either took 50 µg misoprostol orally (two 25 µg tablets) or had one 25 µg tablet of misoprostol inserted in the posterior vaginal fornix. In each group, misoprostol administration was repeated every four hours in the same dose until regular uterine contractions were established or to a maximum of five doses. Time to delivery and outcome data for each group were compared.
RESULTS: Of the 228 women, eight (3.5%) were excluded from the analysis as they withdrew their consent after randomization. Mean induction-to-delivery interval was similar in both groups (21.22 hours in the oral group vs. 20.15 hours in the vaginal group; P = 0.58). There was no significant difference between the groups with respect to the number of women who delivered within 24 hours or who required oxytocin augmentation of labour, the mode of delivery, and neonatal outcomes (P > 0.05). Uterine hyperstimulation occurred in two women who received misoprostol vaginally, but not in any of the women in the oral misoprostol group.
CONCLUSION: Oral misoprostol in a dose of 50 µg every four hours, to a maximum of five doses, has the potential to induce labour as safely and effectively as 25 µg misoprostol administered vaginally every four hours.
METHOD: TVS of the cervix was performed before term labor induction. Induction was considered successful if vaginal delivery was achieved within 24 hours; 231 women were available for final analysis.
RESULTS: Analysis of the receiver operator characteristics curve showed an optimal cut-off for cervical length of < or = 20 mm for successful induction. Following multivariate logistic regression analysis, a sonographic short cervix (AOR 5.6; p < 0.001) was an independent predictor of successful induction but not a favorable Bishop score (p = 0.47). Among multiparas with a short cervix, positive and negative predictive values for successful induction were 98% (95% CI 90-100%) and 21% (95% CI 13%-32%) and among nulliparas, predictive values were 69% (95% CI 53%-82%) and 77% (95% CI 64%-87%) respectively.
CONCLUSION: In nulliparas, cervical length can usefully predict labor induction outcome.
MATERIAL AND METHODS: This was a prospective cohort study conducted in a tertiary referral hospital in Sydney, Australia. In all, 212 women with a low-risk pregnancy or with gestational diabetes were recruited including 158 nulliparous and 54 parous women. Maternal demographic, clinical and ultrasound characteristics were collected at 37 weeks of gestation. Semi-Bayesian logistic regression and Markov chain Monte Carlo simulation were used to assess the relation between cervical length and cesarean section in labor.
RESULTS: Rates of cesarean section were 5% (2/55) for cervical length ≤20 mm, 17% (17/101) for cervical length 20-32 mm, and 27% (13/56) for cervical length >32 mm. These rates were 4, 22 and 33%, respectively, in nulliparous women. In the semi-Bayesian analysis, the odds ratio for cesarean section was 6.2 (95% confidence interval 2.2-43) for cervical length 20-32 mm and 10 (95% confidence interval 4.8-74) for cervical length >32 mm compared with the lowest quartile of cervical length, after adjusting for maternal age, parity, height, prepregnancy body mass index, gestational diabetes, induction of labor, neonatal sex and birthweight centile.
CONCLUSIONS: Cervical length at 37 weeks of gestation is associated with intrapartum cesarean section.
METHODS: We did an individual participant data meta-analysis comparing balloon catheters and vaginal prostaglandins for cervical ripening before labour induction. We systematically identified published and unpublished randomised controlled trials that completed data collection between March 19, 2019, and May 1, 2021, by searching the Cochrane Library, ClinicalTrials.gov, WHO International Clinical Trials Registry Platform, and PubMed. Further trials done before March 19, 2019, were identified through a recent Cochrane review. Data relating to the combined use of the two methods were not included, only data from women with a viable, singleton pregnancy were analysed, and no exclusion was made based on parity or membrane status. We contacted authors of individuals trials and participant-level data were harmonised and recoded according to predefined definitions of variables. Risk of bias was assessed with the ROB2 tool. The primary outcomes were caesarean delivery, indication for caesarean delivery, a composite adverse perinatal outcome, and a composite adverse maternal outcome. We followed the intention-to-treat principle for the main analysis. The primary meta-analysis used two-stage random-effects models and the sensitivity analysis used one-stage mixed models. All models were adjusted for maternal age and parity. This meta-analysis is registered with PROSPERO (CRD42020179924).
FINDINGS: Individual participant data were available from 12 studies with a total of 5460 participants. Balloon catheters, compared with vaginal prostaglandins, did not lead to a significantly different rate of caesarean delivery (12 trials, 5414 women; crude incidence 27·0%; adjusted OR [aOR] 1·09, 95% CI 0·95-1·24; I2=0%), caesarean delivery for failure to progress (11 trials, 4601 women; aOR 1·20, 95% CI 0·91-1·58; I2=39%), or caesarean delivery for fetal distress (10 trials, 4441 women; aOR 0·86, 95% CI 0·71-1·04; I2=0%). The composite adverse perinatal outcome was lower in women who were allocated to balloon catheters than in those allocated to vaginal prostaglandins (ten trials, 4452 neonates, crude incidence 13·6%; aOR 0·80, 95% CI 0·70-0·92; I2=0%). There was no significant difference in the composite adverse maternal outcome (ten trials, 4326 women, crude incidence 22·7%; aOR 1·02, 95% CI 0·89-1·18; I2=0%).
INTERPRETATION: In induction of labour, balloon catheters and vaginal prostaglandins have comparable caesarean delivery rates and maternal safety profiles, but balloon catheters lead to fewer adverse perinatal events.
FUNDING: Australian National Health and Medical Research Council and Monash Health Emerging Researcher Fellowship.
METHODS: : Nulliparas with uncomplicated PROM at term, a Bishop score less than or equal to 6, and who required labor induction were recruited for a double-blind randomized trial. Participants were randomly assigned to 3-mg dinoprostone pessary and oxytocin infusion or placebo and oxytocin infusion. A cardiotocogram was performed before induction and maintained to delivery. Dinoprostone pessary or placebo was placed in the posterior vaginal fornix. Oxytocin intravenous infusion was commenced at 2 milliunits/min and doubled every 30 minutes to a maximum of 32 milliunits/min. Oxytocin infusion rate was titrated to achieve four contractions every 10 minutes. Primary outcomes were vaginal delivery within 12 hours and maternal satisfaction with the birth process using a visual analog scale (VAS) from 0 to 10 (higher score, greater satisfaction).
RESULTS: : One hundred fourteen women were available for analysis. Vaginal delivery rates within 12 hours were 25 of 57 (43.9%) for concurrent treatment compared with 27/57 (47.4%) (relative risk 0.9, 95% confidence interval 0.6-1.4, P=.85) for oxytocin only; median VAS was 8 (interquartile range [IQR] 2) compared with 8 (IQR 2), P=.38. Uterine hyperstimulation was 14% compared with 5.3%, P=.20; overall vaginal delivery rates were 59.6% compared with 64.9%, P=.70; and induction to vaginal delivery interval 9.7 hours compared with 9.4 hours P=.75 for concurrent treatment compared with oxytocin, respectively. There was no significant difference for any other outcome.
CONCLUSION: : Concurrent vaginal dinoprostone and intravenous oxytocin for labor induction of term PROM did not expedite delivery or improve patient satisfaction.
CLINICAL TRIAL REGISTRATION: : Current Controlled Trials, www.controlled-trials.com, ISRCTN74376345
LEVEL OF EVIDENCE: : I.