Misoprostol compared with prostaglandin E2 for labour induction in women at term with intact membranes and unfavourable cervix: a systematic review*

The impact of vaginal pH on induction of labour outcomes: a meta-analysis of observational studies

The present meta-analysis evaluates the impact of an acidic vaginal pH on the progress of labour induction with dinoprostone and misoprostol. We searched Medline, Scopus, EMBASE, Cochrane Central Register of Controlled Trials CENTRAL, Clinicaltrials.gov and Google Scholar databases for relevant studies. Meta-analysis was performed with Rstudio using the meta function and trial sequential analysis was used to evaluate the adequacy of sample size. Nine studies were retrieved that involved 809 patients. An acidic vaginal pH did not influence the efficacy of misoprostol or dinoprostone in terms of accomplishing a successful vaginal delivery (OR 0.62, 95% CI 0.29, 1.30). The interval to delivery was unaffected by the acidity of vaginal pH (Mean Difference 4.18 h, 95% CI -2.09, 10.45). In conclusion, vaginal pH does not seem to affect the potency of vaginally administered prostaglandins; therefore, moistening of vaginal tables with acetic acid does not seem reasonable until further evidence becomes available.

Supraventricular Tachycardia in Infants With Congenital Diaphragmatic Hernia: Prevalence, Associations, and Outcomes

OBJECTIVES

To characterize the prevalence, associations, management, and outcomes of supraventricular tachycardia (SVT) in neonates with congenital diaphragmatic hernia (CDH).

DESIGN

Retrospective chart and cardiology code review within a cohort of patients with CDH was used to define a subpopulation with atrial arrhythmia. SVT mechanisms were confirmed by electrocardiogram analysis. Cox proportional hazard regression identified risk factors for SVT and association with clinical outcomes.

SETTING

Medical Surgical ICU in a single, tertiary center, Boston Children's Hospital.

PATIENTS

Eligible patients included neonates presenting with classic Bochdalek posterolateral CDH between 2005 and 2017, excluding newborns with Morgagni hernia or late diagnoses of CDH (>28 d).

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

SVT arose in 25 of 232 neonates with CDH, (11%); 14 of 25 infants (56%) had recurrent SVT; atrioventricular node-dependent tachycardia was the most frequent mechanism (32%). The majority (71%) of SVT episodes received intervention. Nine patients (36%) received preventative antiarrhythmic medications. SVT was associated with lower Apgar score at 1 min, structural heart disease, larger defect size, extracorporeal membrane oxygenation (ECMO) support, and prostaglandin therapy for ductal patency as well as hospital stay greater than or equal to 8 weeks and use of supplemental oxygen at discharge.

CONCLUSIONS

SVT can occur in neonates with CDH and frequently requires treatment. Odds of occurrence are increased with greater CDH disease severity, ECMO, and prostaglandin use. In unadjusted logistic regression analysis, SVT was associated with adverse hospital outcomes, underscoring the importance of recognition and management in this vulnerable population.

A comparison between induction of labor with 3 methods of titrated oral misoprostol, constant dose of oral misoprostol and Foley catheter with extra amniotic saline infusion (EASI), in women with unfavorable cervix

Background: Different methods of cervical ripening and induction of labor have been used in the cases of unfavorable cervix with different levels of success, but no method has been found to be the best option. The purpose of the present study was to find the effects and side effects of three different methods of cervical ripening and induction of labor. These three methods were oral titrated misoprostol, constant dose of oral misoprostol and Foley catheter with extra-amniotic saline infusion.

Methods: This clinical trial was performed on women with unfavorable cervix who had been admitted in Akbarabadi Teaching Hospital for induction of labor and had bishop score of less than six; between March 2014- March 2015. The eligible women were assigned into three groups. In titrated oral misoprostol group (n=33), titrated solution of misoprostol, and in oral misoprostol group (n=33), 50µg oral misoprostol every four hours and in Foley catheter group (n=50), Foley catheter with extra-amniotic saline infusion were administered. The main outcome was the number of vaginal deliveries during the first 24 hours. In addition, number of cesarean deliveries and adverse effects were compared between the three groups. The obtained data were analyzed using SPSS 18 software. Data analysis was performed according to the intention to treat principle. Chi-square test, Fisher Exact test, Student ttest, and Mann-Whitney U test, were used for comparing data. P-value≤0.05 was considered statistically significant.

Results: The three groups did not have any significant difference according to maternal age, gestational age at the time of admission, gravidity, parity, and primary Bishop Score. There was no significant difference between the three groups for the main outcome, which was vaginal delivery during the first 24 hours (p=0.887). There was no significant difference between the three groups according to hypertonicity, uterine hyperstimulation, meconium passage, non-reassuring fetal heart rate, neonatal Apgar score in minutes one and 5, and mean duration of beginning the intervention up to delivery. However, uterine tachysystole and NICU admission were more in the group to whom the titrated solution of misoprostol was administered (p=0.002 and p=0.037 respectively). The number of cesarean deliveries due to failure to progress was higher in the EASI group. However, EASI group showed the least number of none-reassuring fetal heart rate between the three groups. Meconium passage was more in the titrated misoprostol group, but the difference was not significant.

Conclusion: All three methods are appropriate methods for induction of labor in the cases of unfavorable cervix; and choosing each method depends on the expertise of labor staff, accessibility to the medications, cost, and taking care for monitoring the patients and adverse effects.

Prediction of the induction to delivery time interval in vaginal dinoprostone-induced labor: a retrospective study in a Chinese tertiary maternity hospital

Objective

This study aimed to investigate the potential factors that affect the induction to delivery time interval in women undergoing induction of labor with a controlled-release dinoprostone vaginal insert.

Methods

Pregnant women who presented for delivery at Hubei Maternal and Child Health Hospital from January 2016 to August 2016 were recruited. Finally, 1265 women who underwent labor induction with a vaginal dinoprostone (PGE2) insert were analyzed. Univariate and multivariate linear regression analyses were used to estimate the relevant risks for delivery time.

Results

Among the1265 subjects, the mean delivery time was 18.92 ± 12.50 hours. Univariate and multivariate analyses showed that fetal weight, an obstetric complication (premature rupture of the membranes), and the delivery history were significantly associated with the induction to delivery time. Biparietal diameter was related to the vaginal delivery time in univariate analysis, but there was no significant difference after adjustment in multivariate analysis.

Conclusions

Vaginal dinoprostone is an effective method for successful induction of labor. Gestational age, parity, and fetal weight are major factors that predict the induction to delivery time interval.

Slow-release vaginal insert of misoprostol versus orally administrated solution of misoprostol for the induction of labour in primiparous term pregnant women: a randomised controlled trial

OBJECTIVE

To compare the World Health Organization (WHO) recommended orally administrated dosage of misoprostol (25 μg) with a vaginal slow-release (7 μg/hour) insert of misoprostol regarding time from induction to delivery and safety of the method.

DESIGN

Open label, Randomised controlled trial (RCT).

SETTING

Delivery ward at a secondary referral hospital in Stockholm, Sweden, from 1 October 2016 to 21 February 2018.

POPULATION

One hundred and ninety-six primiparous women with singletons in cephalic presentation at ≥37 weeks of gestation and with a Bishop score of ≤4.

METHODS

Women were randomised to an oral solution of misoprostol (Cytotec^® n = 99) or vaginal slow-release misoprostol (Misodel^® [MVI] n = 97).

MAIN OUTCOME MEASURES

Primary outcome: time from induction to vaginal delivery.

SECONDARY OUTCOMES

mode of delivery; proportion of vaginal deliveries within 24 hours (VD24); neonates with an Apgar score of <7 at 5 minutes; pH < 7.10; postpartum haemorrhage (PPH) of >1000 ml; hyperstimulation; and women's delivery experience (VAS).

RESULTS

There was no difference in the time to delivery [corrected] (median 21.1 hours in the MVI group and 23.2 hours in the oral group; Kaplan-Mayer log rank P = 0.31). There was no difference regarding the proportion of VD24 (50.5 versus 55.7%, P = 0.16). Hyperstimulation with non-reassuring cardiotocography (CTG) was more common in the MVI group (14.4 versus 3.0%, P < 0.01). Terbutaline (Bricanyl^® ) was used more often for hyperstimulation in the MVI group (22.7 versus 4.0%, P < 0.01). There was no difference in the numbers of children admitted to the neonatal intensive care unit (NICU).

CONCLUSIONS

Vaginal delivery after induction of labour (IOL) with slow-release misoprostol did not result in a shorter time from induction to vaginal delivery, compared with oral misoprostol solution, but was associated with a higher risk for hyperstimulation and fetal distress. There were no differences in mode of delivery or neonatal outcome.

TWEETABLE ABSTRACT

IOL with MVI was similar to oral solution of misoprostol but hyperstimulation and fetal distress were more common.

Labor Induction with Orally Administrated Misoprostol: A Retrospective Cohort Study

Introduction

One great challenge in obstetric care is labor inductions. Misoprostol has advantages in being cheap and stable at room temperature and available in resource-poor settings.

Material and Methods

Retrospective cohort study of 4002 singleton pregnancies with a gestational age ≥34 w at Sodersjukhuset, Stockholm, during 2009-2010 and 2012-2013. Previously used methods of labor induction were compared with misoprostol given as a solution to drink, every second hour. Main outcome is as follows: Cesarean Section (CS) rate, acid-base status in cord blood, Apgar score < 7,5′, active time of labor, and blood loss > 1500 ml (PPH).

Results

The proportion of CS decreased from 26% to 17% when orally given solution of misoprostol was introduced at the clinic (p < 0.001). No significant difference in the frequency of low Apgar score (p = 0.3), low aPh in cord blood (p = 0.1), or PPH (p = 0.4) between the different methods of induction was studied. After adjustment for different risk factor for CS the only method of induction which was associated with CS was dinoproston^⁎⁎ (Propess®) (aor = 2.9 (1.6–5.2)).

Conclusion

Induction of labor with misoprostol, given as an oral solution to drink every second hour, gives a low rate of CS, without affecting maternal or fetal outcome.

Contributions to the dynamics of cervix remodeling prior to term and preterm birth

Major clinical challenges for obstetricians and neonatologists result from early cervix remodeling and preterm birth. Complications related to cervix remodeling or delivery account for significant morbidity in newborns and peripartum mothers. Understanding morphology and structure of the cervix in pregnant women is limited mostly to the period soon before and after birth. However, evidence in rodent models supports a working hypothesis that a convergence of factors promotes a physiological inflammatory process that degrades the extracellular collagen matrix and enhances biomechanical distensibility of the cervix well before the uterus develops the contractile capabilities for labor. Contributing factors to this remodeling process include innervation, mechanical stretch, hypoxia, and proinflammatory mediators. Importantly, the softening and shift to ripening occurs while progesterone is near peak concentrations in circulation across species. Since progesterone is required to maintain pregnancy, the premise of this review is that loss of responsiveness to progesterone constitutes a common final mechanism for remodeling the mammalian cervix in preparation for birth at term. Various inputs are suggested to promote signaling between stromal cells and resident macrophages to drive proinflammatory processes that advance the soft cervix into ripening. With infection, pathophysiological processes may prematurely drive components of this remodeling mechanism and lead to preterm birth. Identification of critical molecules and pathways from studies in various rodent models hold promise for novel endpoints to assess risk and provide innovative approaches to treat preterm birth or promote the progress of ripening at term.

Intravaginal Misoprostol for Cervical Ripening and Labor Induction in Nulliparous Women: A Double-blinded, Prospective Randomized Controlled Study

Background:

In China, no multicenter double-blinded prospective randomized controlled study on labor induction has been conducted till now. This study is to evaluate the efficacy and safety of intravaginal accurate 25-μg misoprostol tablets for cervical ripening and labor induction in term pregnancy in nulliparous women.

Methods:

This was a double-blinded, prospective randomized controlled study including nulliparous women from 6 university hospitals across China. Subjects were randomized into misoprostol or placebo group with the sample size ratio set to 7:2. Intravaginal 25-μg misoprostol or placebo was applied at an interval of 4 h (repeated up to 3 times) for labor induction. Primary outcome measures were the incidence of cumulative Bishop score increases ≥3 within 12 h or vaginal delivery within 24 h. Safety assessments included the incidences of maternal morbidity and adverse fetal/neonatal outcomes.

Results:

A total of 173 women for misoprostol group and 49 women for placebo were analyzed. The incidence of cumulative Bishop score increases ≥3 within 12 h or vaginal delivery within 24 h was higher in the misoprostol group than in the placebo (64.2% vs. 22.5%, relative risk [RR]: 2.9, 95% confidence interval [CI]: 1.4–6.0). The incidence of onset of labor within 24 h was significantly higher in the misoprostol group than in the placebo group (48.0% vs. 18.4%, RR: 2.6, 95% CI: 1.2–5.7); and the induction-onset of labor interval was significantly shorter in the misoprostol group (P = 0.0003). However, there were no significant differences in the median process time of vaginal labor (6.4 vs. 6.8 h; P = 0.695), incidence (39.3% vs. 49.0%, RR: 0.8, 95% CI: 0.4–1.5) and indications (P = 0.683) of cesarean section deliveries, and frequencies of maternal, fetal/neonatal adverse events between the groups.

Conclusion:

Intravaginal misoprostol 25 μg every 4 h is efficacious and safe in labor induction and cervical ripening.

Induction of Labor in Post-Term Nulliparous and Parous Women - Potential Advantages of Misoprostol over Dinoprostone

INTRODUCTION

We undertook a prospective cohort study to compare the effectiveness and safety of 50 µg misoprostol versus 3 mg dinoprostone in two vaginal doses 6 hours apart, followed if necessary by oxytocin for labor induction in low-risk post-term (> 40 weeks) pregnancies with unfavorable cervix (Bishop score ≤ 6).

METHODS

Labor induction and subsequent management were conducted using a standardized protocol. The primary outcome of the study was labor induction rate. Secondary outcomes included mode of delivery, time interval from induction to delivery, maternal complications and neonatal outcome.

RESULTS

107 patients received misoprostol (Group A) and 99 patients received dinoprostone (Group B). Compared with group A, more women in Group B needed a second vaginal dose of prostaglandin or oxytocin infusion in order to proceed to labor (21.5 vs. 43.4 %; p = 0.01). Misoprostol alone as a single or double vaginal dose was more effective than dinoprostone alone in inducing labor without oxytocin administration (85.0 vs. 50.4 %; p = 0.04). Overall, the rate of successful induction of labor did not differ between groups (91.6 vs. 85.8 %; p = 0.75). Vaginal delivery, operative vaginal delivery and Caesarean section rates were not significantly different. Time interval from induction to delivery however, was shorter for Group A (median 11 hours vs. 14.1 hours; p < 0.001). Though emergency Caesarean section due to fetal distress was more frequent in Group A (16.8 vs. 4.0 %; p = 0.007), low Apgar scores < 7 and NICU admissions did not differ significantly. Maternal complications, mostly not serious, were higher in Group A (31.8 vs. 2.0, p < 0.001).

CONCLUSION

Misoprostol is a more effective agent than dinoprost in post-term pregnancy for labor induction with few maternal adverse effects.

Effect of Saffron (Fan Hong Hua) On the Readiness of The Uterine Cervix In Term Pregnancy: A Placebo-Controlled Randomized Trial

Background

Readiness of the cervix is required for successful induction of labor, and there are a number of ways in which this can be achieved.

Objectives

The aim of the present study was to assess whether taking saffron orally could have an effect on the cervical readiness (primary outcome) and some delivery and neonatal outcomes (secondary outcomes) in women in the stage of term pregnancy.

Patients and Methods

In this double-blind trial, 50 women with a gestational age of 39 to 41 weeks, no indication of cesarean section, a Bishop’s score of less than 4, who had plan to have vaginal delivery at Shohada hospital of Bonab, Iran were randomized into two groups receiving three 250mg saffron or placebo pills in 24 hours. The readiness of the cervix was assessed using the Bishop’s score. The Mann-Whitney U test was used to compare the scores between the groups.

Results

There were no significant differences between the groups in terms of the Bishop’s score at the baseline (P = 0.792) and 10-12 hours after starting the intervention (P = 0.159). The Bishop’s score was significantly higher in the saffron group 20 - 24 hours after the intervention was started (P = 0.029) and just after onset of active uterine contractions (P = 0.003). In the saffron group, there was no cesarean section and 1 meconium staining of the fetus, but 3 and 4, respectively, in the placebo group. There was no statistically significant difference between the groups in terms of the timing of the onset of spontaneous active uterine contractions, the duration of the first and second stages of labor, the need for delivery augmentation, and the first and fifth minutes of neonatal Apgar (P > 0.05). No adverse event was reported in any of the groups.

Conclusions

Saffron can increase the readiness of the cervix in term pregnancies. However, the study limitations do not allow for any definite conclusions for its use in clinical practice, and more research is needed to assess its effect on delivery and neonatal outcomes.

A randomised double-blind placebo-controlled trial comparing stepwise oral misoprostol with vaginal misoprostol for induction of labour

A comparison of induction of labour (IOL) using three doses of 25 µg vaginal misoprostol inserted at intervals of 4 h or more with a stepwise oral regime starting with 50 µg followed by two doses of 100 µg was studied in a double-blind placebo-controlled trial in a tertiary centre in South India. Primary outcome was vaginal delivery in 24 h. Significantly more women in the first group required oxytocin augmentation and a third dose of the drug than women in the second group. Uterine tachysystole and other maternal and neonatal complications were similar. Thus it is concluded that women induced with oral, as compared to vaginal misoprostol are more likely to labour without oxytocin.

Induction of labor in women with a uterine scar

OBJECTIVE

To evaluate the frequency of uterine rupture following induction of labor in women with a previous cesarean section. Misoprostol was compared to other methods of induction.

METHODS

A retrospective cohort study of 208 women attempting induction of labor after one previous cesarean section. Delivery data were collected retrospectively and compared. Group 1(2009-2010) was compared with Group 2 (2012-2013). In Group 1, the main method of induction was vaginal PGE2 (prostaglandin-E2), amniotomy, oxytocin or a balloon catheter. In Group 2, the dominant method of induction was an oral solution of misoprostol.

MAIN OUTCOME MEASURES

frequency of uterine rupture in the two groups.

RESULTS

Nine cases (4.3%) of uterine rupture occurred. There was no significant difference in the frequency of uterine rupture following the change of method of induction from PGE2, amniotomy, oxytocin or mechanical dilatation with a balloon catheter to orally administered misoprostol (4.1 versus 4.6%, p = 0.9). All ruptures occurred in women with no prior vaginal delivery.

CONCLUSION

The shift to oral misoprostol as the primary method of induction in women with a previous cesarean section did not increase the frequency of uterine rupture in the cohort studied.

Direct electrical stimulation softens the cervix in pregnant and nonpregnant rats

OBJECTIVE

The objective of the study was to determine the effects of electrical stimulation (ES) on cervical ripening in pregnant and nonpregnant rats.

STUDY DESIGN

Timed pregnant and nonpregnant Sprague-Dawley rats (n = 6-7/group) were used. Cervical ES for pregnant rats was performed in vivo on day 15 of gestation by inserting an electrical probe into the vagina in contact with the cervix. Parameters of ES varied from 0.1 to 0.2 mA, 10 pulses per second, 20 milliseconds pulse duration, and repeating pulses for 15, 30, 60, and 120 minutes for pregnant ES groups and similar times for sham control groups with electrode but without ES. Nonpregnant ES groups were stimulated with only 0.2 mA for 30 minutes. Cervical collagen was measured in controls and following ES at various times using light-induced fluorescence (LIF) of collagen. Photographs were taken following ES, and some rats were killed, the cervices were isolated, and cervical extensibility was estimated.

RESULTS

LIF values of pregnant rats are significantly lower (P < .001) and extensibility greater (P < .05) in the ES treatment groups compared with the control groups on days 16 and 17 of pregnancy. Similarly LIF is lower (P < .05) and extensibility values greater (P < .05) in nonpregnant rats treated with ES. No adverse effects, including altered delivery time, pup weights, or damage to cervix, were produced by low current levels of ES needed to soften the cervix.

CONCLUSION

The following conclusions were reached: (1) application of ES rapidly produces softening and ripening of the cervix in pregnant and nonpregnant rats; (2) ES treatment does not produce early delivery; (3) the exact mechanism for ES ripening is not yet known; and (4) ES might be used clinically to ripen the cervix when needed.

Is low dose vaginal misoprostol better than dinoprostone gel for induction of labor: a randomized controlled trial

OBJECTIVE

To compare the efficacy and safety profile of low dose vaginal misoprostol with dinoprostone gel for induction of labor in term pregnancies.

METHODS

The study was conducted at Lady Hardinge Medical College and Smt Sucheta Kriplani Hospital on 100 pregnant women with term pregnancy after application of inclusion and exclusion criteria. The women were randomized in 2 groups of 50 women each. Group I received misoprostol 25μg at every six hour vaginally for a maximum of five doses for induction of labor; while group II received dinoprostone gel 0.5 mg every six hourly for a maximum of three doses. Maternal outcomes such as mode of delivery and induction delivery interval; and fetal outcomes such as APGAR score and incidence of NICU admission were assessed in both the groups. Statistical analysis was done using student t-test and chi-square test.

RESULTS

There was no significant difference in the mean induction to delivery interval in both the groups (14.32±0.13 hours in Group I and 14.92±0.18 hours in Group II, p=0.75), mode of delivery, indication of cesarean section and perinatal outcome. However, significant difference was observed in requirement of oxytocin augmentation in both the groups (32% in Group I and 68% in Group II, p=0.005).

CONCLUSION

Vaginal misoprostol in low doses is similar in efficacy and safety to dinoprostone gel for cervical ripening and labor induction in term pregnancy.

Induction of labour

OBJECTIVE

To review the most current literature in order to provide evidence-based recommendations to obstetrical care providers on induction of labour.

OPTIONS

Intervention in a pregnancy with induction of labour.

OUTCOMES

Appropriate timing and method of induction, appropriate mode of delivery, and optimal maternal and perinatal outcomes.

EVIDENCE

Published literature was retrieved through searches of PubMed, CINAHL, and The Cochrane Library in 2010 using appropriate controlled vocabulary (e.g., labour, induced, labour induction, cervical ripening) and key words (e.g., induce, induction, augmentation). Results were restricted to systematic reviews, randomized control trials/controlled clinical trials, and observational studies. There were no date or language restrictions. Searches were updated on a regular basis and incorporated in the guideline to the end of 2010. Grey (unpublished) literature was identified through searching the websites of health technology assessment and health technology-related agencies, clinical practice guideline collections, clinical trial registries, and national and international medical specialty societies.

VALUES

The evidence in this document was rated using criteria described in the Report of the Canadian Task Force on Preventative Health Care (Table 1). SUMMARY STATEMENTS: 1. Prostaglandins E(2) (cervical and vaginal) are effective agents of cervical ripening and induction of labour for an unfavourable cervix. (I) 2. Intravaginal prostaglandins E(2) are preferred to intracervical prostaglandins E(2) because they results in more timely vaginal deliveries. (I).

Current pharmacotherapy options for labor induction

INTRODUCTION

Labor induction is now reported to occur in up to 30 - 40% of obstetrical patients. There are a number of pharmacological options available to facilitate labor induction, including oxytocin and analogues of prostaglandins E1 and E2, which have particular utility when labor induction necessitates cervical ripening, as when labor induction occurs in the context of an unfavorable cervix.

AREAS COVERED

This paper reviews acceptable pharmacological options for labor induction, especially when cervical ripening is required. These options include oxytocin and a number of prostaglandin formulations using dinoprostone and misoprostol. It also covers several analyses of published clinical trials (Phase-III) describing evidence of effectiveness.

EXPERT OPINION

Oxytocin is best used when labor needs to be induced in the context of a favorable cervix. When the cervix is not favorable, cervical ripening using prostaglandins should precede labor induction. Either dinoprostone or misoprostol are superior to oxytocin alone for cervical ripening. However, judicious, careful considerations need to be made at the outset of labor induction so as to balance maternal and fetal risks, and these should be guided by institutional policies that reflect the evidence-base.

Induction of labor in prolonged pregnancy with unfavorable cervix: comparison of sequential intracervical Foley catheter-intravaginal misoprostol and intravaginal misoprostol alone

PURPOSE

To compare the outcome of induced labor at term using sequential intracervical Foley catheter with intravaginal misoprostol versus intravaginal misoprostol alone.

METHODS

A prospective matched case control study among parturient with prolonged pregnancy and unfavorable cervix at a tertiary hospital in Nigeria.

RESULTS

The study population was 100 with a mean age of 29.46 ± 3.88 years. Parturient with prior cervical priming using intracervical Foley catheter had significantly lower oxytocin augmentation of uterine contractions in labor (44 vs. 64%, P = 0.045), shorter mean insertion to active phase labor duration (233 ± 98 vs. 354 ± 154 min, P = 0.0001), shorter insertion to delivery interval (514 ± 175 vs. 627 ± 268, P = 0.014), more vaginal delivery <12 h (92.5 vs. 60%, P = 0.001) and less delivery by caesarean section (20 vs. 40%, P = 0.029).

CONCLUSIONS

The sequential combination of intracervical Foley catheter and intravaginal misoprostol for cervical ripening and induction of labor appears to be a safe and more effective method compared to intravaginal misoprostol in parturient at term with unfavorable cervices.

A randomised controlled trial of low-dose misoprostol and dinoprostone vaginal pessaries for cervical priming

OBJECTIVE

We studied the efficacy of 25-microg misoprostol pessaries as either single or double dose compared with a 3-mg dinoprostone pessary for cervical priming.

DESIGN AND SETTING

A randomised controlled trial in Singapore.

POPULATION

One hundred and seventy-one women with term pregnancies and modified Bishop scores (mBS) < or =6 from 2003 to 2004.

METHOD

Patients were randomised to single misoprostol dose, double misoprostol dose or the current dinoprostone regimen.

MAIN OUTCOME MEASURES

Primary outcome was number of women who achieved favourable mBS >6 or active labour by day 2. Secondary outcomes were time interval from insertion to delivery, cardiotocographic abnormalities, delivery and neonatal outcome.

RESULTS

More women in the misoprostol double-dose group (96.6%) and dinoprostone group (93%) achieved the primary outcome compared with the single-dose group (77.8%) (P = 0.003 and P = 0.03, respectively). There was no difference in secondary outcomes. More multiparous women achieve primary outcome compared with nulliparous women (odds ratio 0.21, 95% confidence interval 0.06-0.77).

CONCLUSION

Double-dose misoprostol 25 microg is as effective as dinoprostone 3 mg inserts for cervical priming; both are more efficacious than a single-dose misoprostol pessary. Parity prognosticates the success of induction.

Pre-induction cervical ripening with 25 microg and 50 microg vaginal misoprostol in 181 nulliparous parturients

OBJECTIVE

To evaluate the effect of intravaginally misoprostol at start dosages of 25 microg and 50 microg when used for pre-induction cervical ripening among nulliparous parturients.

METHODS

Our observational study involves all cases of partus induction consecutively registered in a Norwegian hospital between September 2002 and August 2006, with the following inclusion criteria: nulliparous, singleton pregnancies >or=37 weeks, an unfavourable cervix (Bishop score <or=6), viable fetus >2499 g, received misoprostol vaginally every 6 h upto four times. Seventy-six women started with 25 microg (25 microg-group) and 105 started with 50 microg (50 microg-group). All continued with 25 microg. Primary outcome was vaginal delivery within 48 h after the first misoprostol dose. Secondary outcome was caesarean section performed within 96.

RESULTS

Vaginal delivery within 48 h after the initial dose occurred more often in the 25 microg-group than in the 50 microg-group (75 vs. 58%, p = 0.018). The rate of caesarean section was lower in the 25 microg-group than in the 50 microg-group (19 vs. 33%, p = 0.043). These differences remained significant after adjusting for confounders.

CONCLUSION

Our findings support the notion that the dose of 25 microg misoprostol is as at least as efficient as 50 microg in nulliparous parturients.

Low-dose oral misoprostol for induction of labor: a systematic review

OBJECTIVE

To estimate the efficacy and safety of low-dose oral misoprostol compared with dinoprostone (PGE2), vaginal misoprostol, and oxytocin for labor induction in women with a viable fetus.

DATA SOURCES

We conducted electronic database searches of PubMed, MEDLINE, EMBASE, and the Cochrane Library for articles published before January 2008 using the keywords misoprostol, labor, induction, randomized controlled trials, dinoprostone, oxytocin, pregnancy, and maternal and fetal side effects.

METHODS OF STUDY SELECTION

We included randomized controlled trials comparing 20-25 micrograms oral misoprostol with vaginal misoprostol, dinoprostone or oxytocin given to women at 32-42 weeks of gestation for labor induction. From 401 citations identified, results from nine studies were finally analyzed using the Review Manager software. Relative risk (RR) and 95% confidence intervals (CIs) were calculated using fixed and random-effects models.

TABULATION, INTEGRATION, AND RESULTS

Nine articles with 2,937 women met the inclusion criteria. The five trials comparing oral misoprostol and dinoprostone showed significantly fewer women requiring cesarean delivery in the misoprostol group (20% compared with 26%; RR 0.82, 95% CI 0.71-0.96). There were no statistically significant differences in risks of uterine hyperstimulation or need for oxytocin augmentation. Two trials compared oral with vaginal low-dose misoprostol. Women using oral misoprostol were significantly less likely to experience uterine hyperstimulation with fetal heart rate changes (2% compared with 13%; RR 0.19, 95% CI 0.08-0.46), but there were no significant differences in other outcomes.

CONCLUSION

Low-dose oral misoprostol solution (20 micrograms) administered every 2 hours seems at least as effective as both vaginal dinoprostone and vaginal misoprostol, with lower rates of cesarean delivery and uterine hyperstimulation, respectively.

A randomised controlled trial of intravaginal dinoprostone, intravaginal misoprostol and transcervical balloon catheter for labour induction

OBJECTIVE

To compare the efficacy and safety of induction of labour by vaginal application of dinoprostone or misoprostol or transcervical insertion of a balloon (Bard) catheter.

DESIGN

A non-blinded, randomised, controlled trial.

SETTING

A tertiary level Swedish hospital.

POPULATION

A total of 592 women who had undergone full-term pregnancies, not previously been subjected to a caesarean section, and required induction of labour for common, routine indications.

METHODS

Women were randomly assigned to induction of labour using intravaginal dinoprostone (2 mg once every 6 hours) or misoprostol (25 micrograms once every 4 hours) or a transcervical balloon catheter.

MAIN OUTCOME MEASURES

The time interval between induction to delivery in general and vaginal delivery in particular, the mode of delivery, maternal and neonatal parameters of outcome.

RESULTS

Of the 588 subjects included in the final intention-to-treat analysis, 191 were assigned to treatment with dinoprostone, 199 with misoprostol and 198 with the balloon catheter. The shortest mean induction-to-delivery interval was obtained with the catheter (12.9 hours versus 16.8 and 17.3 hours for dinoprostone and misoprostol, respectively). The efficacies of the two prostaglandins were similar. The maternal and neonatal outcomes associated with each of the three procedures were similar.

CONCLUSIONS

Induction of labour with a transcervical balloon catheter is effective and safe and can be recommended as the first choice. The two prostaglandins, dinoprostone and misoprostol, were shown to be equally effective and safe, while misoprostol costs significantly less and is easier to store.

Exploring heterogeneity in meta-analyses: needs, resources and challenges

The investigation of heterogeneity remains an essential but difficult issue in the conduct of meta-analysis. We reviewed standard and graphical methods used to explore heterogeneity in meta-analysis and publications from January 2005 to April 2007 regarding meta-analyses that focused on perinatal health topics. We assessed their approaches to the investigation of heterogeneity, including: (1) whether statistical testing for heterogeneity was performed and, if so, which test was used, (2) how a finding of statistically significant heterogeneity was handled, and (3) how the analyses were conducted in the presence of heterogeneity.

Tailoring systematic reviews to meet critical priorities in maternal health in the intrapartum period

Health care practitioners and researchers commonly call for greater reliance on evidence as a means to achieve improvement in quality of care. Systematic reviews provide a means to accelerate the use of evidence-based clinical interventions and public health practices. The extent to which these time- and resource-intensive systematic reviews currently address critical maternal health priorities in the intrapartum period is unclear. This analysis summarises key maternal health and research priorities, maps these priorities to existing reviews, identifies gaps in the literature that can be addressed with systematic reviews, and highlights key methodological concerns in conducting systematic reviews. The analysis draws on published data on maternal morbidities and an overview of 108 systematic reviews in Medline in the past 5 years using the MeSH terms 'Delivery, Obstetric,' to draw the links between health priorities, research priorities, existing evidence and missing evidence. Key causes of morbidity during labour and delivery in the United States include haemorrhage, pre-eclampsia and eclampsia, obstetric trauma and infection. Analyses of maternal morbidity and mortality suggest that key concerns include racial and ethnic disparities in health outcomes and the prevention of adverse events. Systematic reviews, however, generally tend to focus on the reduction of harms associated with interventions, are frequently limited to randomised designs, and do not address issues of health disparities. The results suggest that advances in evidence-based care in maternal health require that systematic reviews address issues of prevention of adverse events, include a larger variety of study designs when necessary and pay closer attention to health disparities.