Concept: Labor induction
To determine if “early rupture of membranes” (early ROM) during induction of labor is associated with an increased risk of cesarean section in term nulliparas.
BACKGROUND: British women are increasingly delaying childbirth. The proportion giving birth over the age of 35 rose from 12% in 1996 to 20% in 2006. Women over this age are at a higher risk of perinatal death, and antepartum stillbirth accounts for 61% of all such deaths. Women over 40 years old have a similar stillbirth risk at 39 weeks as women who are between 25 and 29 years old have at 41 weeks.Many obstetricians respond to this by suggesting labour induction at term to forestall some of the risk. In a national survey of obstetricians 37% already induce women aged 40–44 years. A substantial minority of parents support such a policy, but others do not on the grounds that it might increase the risk of Caesarean section. However trials of induction in other high-risk scenarios have not shown any increase in Caesarean sections, rather the reverse. If induction for women over 35 did not increase Caesareans, or even reduced them, it would plausibly improve perinatal outcome and be an acceptable intervention. We therefore plan to perform a trial to test the effect of such an induction policy on Caesarean section rates.This trial is funded by the NHS Research for Patient Benefit (RfPB) Programme. DESIGN: The 35/39 trial is a multi-centre, prospective, randomised controlled trial. It is being run in twenty UK centres and we aim to recruit 630 nulliparous women (315 per group) aged over 35 years of age, over two years. Women will be randomly allocated to one of two groups:Induction of labour between 390/7 and 396/7 weeks gestation.Expectant management i.e. awaiting spontaneous onset of labour unless a situation develops necessitating either induction of labour or Caesarean Section.The primary purpose of this trial is to establish what effect a policy of induction of labour at 39 weeks for nulliparous women of advanced maternal age has on the rate of Caesarean section deliveries. The secondary aim is to act as a pilot study for a trial to answer the question, does induction of labour in this group of women improve perinatal outcomes? Randomisation will occur at 360/7 – 396/7 weeks gestation via a computerised randomisation programme at the Clinical Trials Unit, Nottingham University Hospitals NHS Trust. There will be no blinding to treatment allocation. DISCUSSION: The 35/39 trial is powered to detect an effect of induction of labour on the risk of caesarean section, it is underpowered to determine whether it improves perinatal outcome. The current study will also act as a pilot for a larger study to address this question.Trial registration: ISRCTN11517275.
Objective To assess the ability of the Bishop score to predict the mode of delivery in women scheduled for induction of labor at term.Study Design We performed a systematic literature search of electronic databases from inception to July 2009. Studies reporting on both the Bishop score and the outcome of labor in women scheduled for induction of labor at term were eligible. We used a bivariate model to estimate a summary receiver operating characteristic (sROC) curve for the outcome cesarean delivery.Results We included 40 primary articles reporting on 13,757 women. Study quality was mediocre. The sROC curve of the Bishop score in the prediction of cesarean delivery indicated a poor predictive capacity. For the prediction of cesarean delivery, the sensitivity-specificity combinations were 47%-75%, 61%-53% and 78%-44% for the Bishop scores of 4, 5, and 6, respectively. For a Bishop score below 9, the sensitivity-specificity combination was 95%-30%.Conclusion The Bishop score is a poor predictor for the outcome of induced labor at term and should not be used to decide whether to induce labor or not.
Indications for operative delivery between 1999-2010 and induction of labor and epidural analgesia on the risk of operative delivery - A population based Swedish register study.
- Sexual & reproductive healthcare : official journal of the Swedish Association of Midwives
- Published about 6 years ago
The aim of this study was to describe the distribution of indications for vacuum extraction (VE) and emergency cesarean section (EMCS) from 1999 to 2010. Furthermore, we investigated the association of induction of labor and epidural analgesia (EA) on the risk of operative delivery.
The purpose of this study was to determine whether there is an increase in the cesarean delivery rate in women who undergo induction when oxytocin is discontinued in the active phase of labor.
OBJECTIVE: To estimate the association between elective induction of labor and cesarean section in low-risk parous women, and to assess if the association is influenced by induction method. DESIGN: Cohort study. SETTING: University hospital in Sweden. Population Parous women without pregnancy complications or previous cesarean section, and with a planned vaginal term (37-41 weeks), singleton birth, in vertex position were included. METHODS: Information was collected from a local database containing prospectively entered antenatal and delivery data. Odds ratios for cesarean section were calculated using generalized estimating equations logistic regression and adjusted for parity, maternal age, gestational length, birthweight, use of epidural anesthesia and year of birth. MAIN OUTCOME MEASURE: Emergency cesarean section. RESULTS: Among 7973 pregnancies that fulfilled the inclusion criteria, 343 (4%) had an elective induction of labor. Intravenous oxytocin was administered in 5% of these inductions, amniotomy was performed in 62%, and a cervical ripening agent was used in 33%. Electively induced labor more than doubled the risk of cesarean section compared with spontaneous labor onset (OR 2.5, 95% 1.4-4.2) and this risk was more than tripled when cervical ripening was used (OR 3.6, 95% confidence interval 1.7-7.6). CONCLUSIONS: In low-risk parous women, electively induced labor has an increased risk of emergency cesarean section compared with spontaneous onset labor. This risk increase is more pronounced if cervical ripening agents are required. Women need to be counseled about these risks before elective induction of delivery is decided. © 2012 The Authors Acta Obstetricia et Gynecologica Scandinavica © 2012 Nordic Federation of Societies of Obstetrics and Gynecology.
OBJECTIVE: To evaluate the efficacy and safety of prophylactic misoprostol use at cesarean delivery for reducing intraoperative and postoperative hemorrhage. STUDY DESIGN: Systematic review and meta-analysis of randomized controlled trials. RESULTS: Seventeen studies (3174 women) were included of which 7 evaluated misoprostol versus oxytocin and 8 evaluated misoprostol plus oxytocin versus oxytocin. Overall, there were no significant differences in intraoperative and postoperative hemorrhage between sublingual or oral misoprostol and oxytocin. Rectal misoprostol, compared with oxytocin, was associated with a significant reduction in intraoperative and postoperative hemorrhage. The combined use of sublingual misoprostol and oxytocin, compared with the use of oxytocin alone, was associated with a significant reduction in the mean decrease in hematocrit (mean difference, -2.1%; 95% confidence interval [CI], -3.4 to -0.8) and use of additional uterotonic agents (relative risk, 0.33; 95% CI, 0.18-0.62). Compared with oxytocin alone, buccal misoprostol plus oxytocin reduced the use of additional uterotonic agents; rectal misoprostol plus oxytocin decreased intraoperative and postoperative blood loss, mean fall in hematocrit, and use of additional uterotonic agents; and intrauterine misoprostol plus oxytocin reduced the mean fall in hemoglobin and hematocrit. Women receiving misoprostol, alone or combined with oxytocin, had a higher risk of shivering and pyrexia. CONCLUSION: Misoprostol combined with oxytocin appears to be more effective than oxytocin alone in reducing intraoperative and postoperative hemorrhage during caesarean section. There were no significant differences in intraoperative and postoperative hemorrhage when misoprostol was compared to oxytocin. However, these findings were based on a few trials with methodological limitations.
Abstract Objectives: To find an effective way to predict cesarean section (CS) before induction of labor. Methods: Nulliparous women at ≥41 weeks of pregnancy were enrolled in study. Bishop score, cervical length, posterior cervical angle, quantification of the cervical stromal echogenity by tissue histograms and opening of the internal cervical os (Funnelling) were recorded. The vaginal delivery and CS groups were then compared in terms of the clinical and ultrasonographic cervical findings. Results: Bishop score, cervical length, posterior cervical angle and funnelling were significant predictors of CS whereas no such relationship existed for the quantitave echogenity of the cervical stroma. Although the difference was not statistically significant, the area under the curve was higher for the Bishop score than the sonographic cervical length and posterior cervical angle in the prediction of all cesarean sections. The best cut-off values to predict CS for Bishop score, cervical length and posterior cervical angle were <5, >27 mm and <98 degrees respectively. Combination of all three parameters had a sensitivity of 83.3%, specificity of 100 %, positive predictive value (PPV) of 100 % and negative predictive value (NPV) of 82% for the prediction of CS. Conclusions: In nulliparous women with prolonged pregnancy the Bishop score predicts the need for CS better than the ultrasonographic assessment of the cervix.
OBJECTIVES: To test the effectiveness and safety of early amniotomy after vaginal misoprostol for the induction of labor. STUDY DESIGN: A randomized clinical trial that included 320 women with medical or obstetric indication for labor induction. They were randomly assigned into two equal groups, amniotomy group and control group. Each participant received vaginal misoprostol 50 μg every 6 h for induction of labor. In amniotomy group, amniotomy was done in the early active phase of labor while in the control group, the membranes were left to rupture spontaneously or as judged by the senior resident in the duty. RESULTS: More subjects in the amniotomy group achieved vaginal delivery within 24 h than in the control group [117 (73.13 %) vs. 105 (65.63 %)]. Subjects in the amniotomy group reported shorter induction to delivery interval (09.72 ± 4.61 h vs. 13.61 ± 5.61, P = .002), and better neonatal outcome compared to the control group. There were no statistically significant differences between both group with regard to number of doses of misoprostol, need for oxytocin, Cesarean Section indication and maternal side effects. CONCLUSION: Early amniotomy after vaginal misoprostol for labor induction is associated with higher successful vaginal delivery rate, shorter labor duration and better neonatal outcome.
Single indications of induction of labor with prostaglandins and risk of cesarean delivery: A retrospective cohort study
- The journal of obstetrics and gynaecology research
- Published about 6 years ago
AIM: To determine the risk of cesarean delivery after induction of labor with prostaglandins and to establish if this is influenced by a single indication of induction of labor or any intrinsic characteristic of the woman or labor. MATERIAL AND METHODS: A retrospective cohort study was carried out. Three hundred and twenty-four pregnant women who underwent pharmacological induction of labor with prostaglandins were divided into nine groups through indication of labor induction. Statistical analysis was assessed with the Kolmogorov-Smirnov test to assess the normal distribution of variables, Kruskal-Wallis test for comparisons of non-parametric continuous variables, univariate analysis to compare cesarean delivery rates and multivariate logistic regression. RESULTS: The risk of cesarean section was significantly higher only in prolonged pregnancy (OR = 1.98; 95% CI: 1.18-3.34). Elective induction was associated with the lowest risk of cesarean section (OR = 0.46; 95% CI: 0.26-0.81). Maternal age and was directly related (OR = 1.087; 95% CI: 1.016-1.164), while parity (OR = 0.123; 95% CI: 0.051-0.332), Bishop score (OR = 0.703; 95% CI: 0.571-0.884), and duration of labor (OR = 0.995; 95% CI: 0.993-0.998) were inversely correlated with cesarean delivery. CONCLUSION: Cesarean delivery rate is not significantly influenced by any indication of induction of labor with prostaglandins, except for prolonged pregnancy. Elective induction is associated with the lowest risk of cesarean section. Increasing maternal age, low parity, low Bishop score and low duration of labor are at higher risk of cesarean section.