A Comparison of Vaginal vs. Oral Misoprostol for Induction of Labor-Double Blind Randomized Trial

Evidence Based Management of Labor

Importance

Induction of labor (IOL) is a common obstetric intervention. Augmentation of labor and active management of the second stage is frequently required in obstetric practice. However, techniques around labor and induction management vary widely. Evidence-based practice regarding induction and labor management can reduce birth complications such as infection and hemorrhage and decrease rates of cesarean delivery.

Objective

To review existing evidence on IOL and labor management strategies with respect to preparing for induction, cervical ripening, induction and augmentation, and second stage of labor techniques.

Evidence acquisition

Review of recent original research, review articles, and guidelines on IOL using PubMed (2000-2022).

Results

Preinduction, pelvic floor training and perineal massage reduce postpartum urinary incontinence and perineal trauma, respectively. Timely membrane sweeping (38 weeks) can promote spontaneous labor and prevent postterm inductions. Outpatient Foley bulb placement in low-risk nulliparous patients with planned IOL reduces time to delivery. Inpatient Foley bulb use beyond 6 to 12 hours shows no benefit. When synthetic prostaglandins are indicated, vaginal misoprostol should be preferred. For nulliparous patients and those with obesity, oxytocin should be titrated using a high-dose protocol. Once cervical dilation is complete, pushing should begin immediately. Warm compresses and perineal massage decrease risk of perineal trauma.

Conclusion and relevance

Several strategies exist to assist in successful IOL and promote vaginal delivery. Evidence-based strategies should be used to improve outcomes and decrease risk of complications and cesarean delivery. Recommendations should be shared across interdisciplinary team members, creating a model that promotes safe patient care.

Efficacy and safety of oral and sublingual versus vaginal misoprostol for induction of labour: a systematic review and meta-analysis

Objective

Misoprostol is a synthetic PGE1 analogue that is used for induction of labour. Current guidelines support the use of doses that do not exceed 25 mcg in order to limit maternal and neonatal adverse outcomes. The present meta-analysis investigates the efficacy and safety of oral compared to vaginally inserted misoprostol in terms of induction of labor and adverse peripartum outcomes.

Methods

We searched Medline, Scopus, the Cochrane Central Register of Controlled Trials CENTRAL, Google Scholar, and Clinicaltrials.gov databases from inception till April 2022. Randomized controlled trials that assessed the efficacy of oral misoprostol (per os or sublingual) compared to vaginally inserted misoprostol. Effect sizes were calculated in R. Sensitivity analysis was performed to evaluate the possibility of small study effects, p-hacking. Meta-regression and subgroup analysis according to the dose of misoprostol was also investigated. The methodological quality of the included studies was assessed by two independent reviewers using the risk of bias 2 tool. Quality of evidence for primary outcomes was evaluated under the Grading of Recommendations Assessment, Development and Evaluation (GRADE) framework, ranging from very low to high.

Results

Overall, 57 studies were included that involved 10,975 parturient. Their risk of bias ranged between low-moderate. There were no differences among the routes of intake in terms of successful vaginal delivery within 24 h (RR 0.90, 95% CI 0.80) and cesarean section rates (RR 0.92, 95% CI 0.82, 1.04). Sublingual misoprostol was superior compared to vaginal misoprostol in reducing the interval from induction to delivery (MD – 1.11 h, 95% CI – 2.06, – 0.17). On the other hand, per os misoprostol was inferior compared to vaginal misoprostol in terms of this outcome (MD 3.45 h, 95% CI 1.85, 5.06). Maternal and neonatal morbidity was not affected by the route or dose of misoprostol.

Conclusion

The findings of our study suggest that oral misoprostol intake is equally safe to vaginal misoprostol in terms of inducing labor at term. Sublingual intake seems to outperform the per os and vaginal routes without increasing the accompanying morbidity. Increasing the dose of misoprostol does not seem to increase its efficacy.

Clinical trial registration

Open Science Framework (https://doi.org/10.17605/OSF.IO/V9JHF).

Sequential use of drugs (prostaglandin e1 after failed trial of PGE2 gel) for induction of labour: Retrospective observational study

With advancements in medicine, the scope of pregnancies have increased. This has subsequently increased the number of inductions and therefore more caesarean sections. We looked at the efficacy and safety of sequential induction with PGE2 gel followed by PGE1 tablets after a period of rest in a retrospective observational study. Women with failed induction of labour with 3 PGE2 gel were re-induced with 25ug vaginal PGE1 tablets, with a maximum of five doses (sequential regimen). Fetomaternal outcome and vaginal delivery rates were compared between the only-PGE2 gel group and the sequential group.There were 296 inductions of labour, of which 41 were included in the sequential group, amongst whom the vaginal delivery rate was 56%. Caesarean delivery rate with only PGE2 gel would have been 32%, but with the addition of PGE1 vaginal tablet (sequential induction), it reduced by >8% (p  =  0.02). Fetomaternal outcomes were comparable in the two groups. We thus conclude that sequential induction with PGE1 tablets is an effective option.

Low-dose oral misoprostol for induction of labour

BACKGROUND

Misoprostol given orally is a commonly used labour induction method. Our Cochrane Review is restricted to studies with low-dose misoprostol (initially ≤ 50 µg), as higher doses pose unacceptably high risks of uterine hyperstimulation.

OBJECTIVES

To assess the efficacy and safety of low-dose oral misoprostol for labour induction in women with a viable fetus in the third trimester of pregnancy.

SEARCH METHODS

We searched Cochrane Pregnancy and Childbirth's Trials Register, ClinicalTrials.gov,  the WHO International Clinical Trials Registry Platform (14 February 2021) and reference lists of retrieved studies.

SELECTION CRITERIA

Randomised trials comparing low-dose oral misoprostol (initial dose ≤ 50 µg) versus placebo, vaginal dinoprostone, vaginal misoprostol, oxytocin, or mechanical methods; or comparing oral misoprostol protocols (one- to two-hourly versus four- to six-hourly; 20 µg to 25 µg versus 50 µg; or 20 µg hourly titrated versus 25 µg two-hourly static).

DATA COLLECTION AND ANALYSIS

Using Covidence, two review authors independently screened reports, extracted trial data, and performed quality assessments. Our primary outcomes were vaginal birth within 24 hours, caesarean section, and hyperstimulation with foetal heart changes.

MAIN RESULTS

We included 61 trials involving 20,026 women. GRADE assessments ranged from moderate- to very low-certainty evidence, with downgrading decisions based on imprecision, inconsistency, and study limitations. Oral misoprostol versus placebo/no treatment (four trials; 594 women) Oral misoprostol may make little to no difference in the rate of caesarean section (risk ratio (RR) 0.81, 95% confidence interval (CI) 0.59 to 1.11; 4 trials; 594 women; moderate-certainty evidence), while its effect on uterine hyperstimulation with foetal heart rate changes is uncertain (RR 5.15, 95% CI 0.25 to 105.31; 3 trials; 495 women; very low-certainty evidence). Vaginal births within 24 hours was not reported. In all trials, oxytocin could be commenced after 12 to 24 hours and all women had pre-labour ruptured membranes. Oral misoprostol versus vaginal dinoprostone (13 trials; 9676 women) Oral misoprostol probably results in fewer caesarean sections (RR 0.84, 95% CI 0.78 to 0.90; 13 trials, 9676 women; moderate-certainty evidence). Subgroup analysis indicated that 10 µg to 25 µg (RR 0.80, 95% CI 0.74 to 0.87; 9 trials; 8652 women) may differ from 50 µg (RR 1.10, 95% CI 0.91 to 1.34; 4 trials; 1024 women) for caesarean section. Oral misoprostol may decrease vaginal births within 24 hours (RR 0.93, 95% CI 0.87 to 1.00; 10 trials; 8983 women; low-certainty evidence) and hyperstimulation with foetal heart rate changes (RR 0.49, 95% CI 0.40 to 0.59; 11 trials; 9084 women; low-certainty evidence). Oral misoprostol versus vaginal misoprostol (33 trials; 6110 women) Oral use may result in fewer vaginal births within 24 hours (average RR 0.81, 95% CI 0.68 to 0.95; 16 trials, 3451 women; low-certainty evidence), and less hyperstimulation with foetal heart rate changes (RR 0.69, 95% CI 0.53 to 0.92, 25 trials, 4857 women, low-certainty evidence), with subgroup analysis suggesting that 10 µg to 25 µg orally (RR 0.28, 95% CI 0.14 to 0.57; 6 trials, 957 women) may be superior to 50 µg orally (RR 0.82, 95% CI 0.61 to 1.11; 19 trials; 3900 women). Oral misoprostol probably does not increase caesarean sections overall (average RR 1.00, 95% CI 0.86 to 1.16; 32 trials; 5914 women; low-certainty evidence) but likely results in fewer caesareans for foetal distress (RR 0.74, 95% CI 0.55 to 0.99; 24 trials, 4775 women). Oral misoprostol versus intravenous oxytocin (6 trials; 737 women, 200 with ruptured membranes) Misoprostol may make little or no difference to vaginal births within 24 hours (RR 1.12, 95% CI 0.95 to 1.33; 3 trials; 466 women; low-certainty evidence), but probably results in fewer caesarean sections (RR 0.67, 95% CI 0.50 to 0.90; 6 trials; 737 women; moderate-certainty evidence). The effect on hyperstimulation with foetal heart rate changes is uncertain (RR 0.66, 95% CI 0.19 to 2.26; 3 trials, 331 women; very low-certainty evidence). Oral misoprostol versus mechanical methods (6 trials; 2993 women) Six trials compared oral misoprostol to transcervical Foley catheter. Misoprostol may increase vaginal birth within 24 hours (RR 1.32, 95% CI 0.98 to 1.79; 4 trials; 1044 women; low-certainty evidence), and probably reduces the risk of caesarean section (RR 0.84, 95% CI 0.75 to 0.95; 6 trials; 2993 women; moderate-certainty evidence). There may be little or no difference in hyperstimulation with foetal heart rate changes (RR 1.31, 95% CI 0.78 to 2.21; 4 trials; 2828 women; low-certainty evidence). Oral misoprostol one- to two-hourly versus four- to six-hourly (1 trial; 64 women) The evidence on hourly titration was very uncertain due to the low numbers reported. Oral misoprostol 20 µg hourly titrated versus 25 µg two-hourly static (2 trials; 296 women) The difference in regimen may have little or no effect on the rate of vaginal births in 24 hours (RR 0.97, 95% CI 0.80 to 1.16; low-certainty evidence). The evidence is of very low certainty for all other reported outcomes.

AUTHORS' CONCLUSIONS

Low-dose oral misoprostol is probably associated with fewer caesarean sections (and therefore more vaginal births) than vaginal dinoprostone, and lower rates of hyperstimulation with foetal heart rate changes. However, time to birth may be increased, as seen by a reduced number of vaginal births within 24 hours. Compared to transcervical Foley catheter, low-dose oral misoprostol is associated with fewer caesarean sections, but equivalent rates of hyperstimulation. Low-dose misoprostol given orally rather than vaginally is probably associated with similar rates of vaginal birth, although rates may be lower within the first 24 hours. However, there is likely less hyperstimulation with foetal heart changes, and fewer caesarean sections performed due to foetal distress. The best available evidence suggests that low-dose oral misoprostol probably has many benefits over other methods for labour induction. This review supports the use of low-dose oral misoprostol for induction of labour, and demonstrates the lower risks of hyperstimulation than when misoprostol is given vaginally. More trials are needed to establish the optimum oral misoprostol regimen, but these findings suggest that a starting dose of 25 µg may offer a good balance of efficacy and safety.

Factors associated with delayed onset of active labor following vaginal misoprostol administration among women at Mbarara Regional Referral Hospital, Uganda

OBJECTIVE

To determine the factors associated with delayed onset of active labor following labor induction with vaginal misoprostol.

METHODS

We conducted a prospective cohort study over 6 months at a tertiary hospital in Uganda. We enrolled mothers with pregnancies of at least 28 weeks, who were undergoing labor induction with 50 µg of vaginal misoprostol, administered every 6 hours with a maximum of four doses, and followed them up until onset of active labor. Labor onset was considered delayed if it occurred later than 12 hours after the first dose. Bivariate and multivariate analysis was performed to determine factors associated with delayed onset of active labor.

RESULTS

Of the 88 mothers enrolled, 22.7% (n=20) had delayed onset of active labor. Nulliparity (adjusted relative risk [aRR] 2.34, 95% confidence interval [CI] 1.17-4.68) and gestational age less than 37 weeks (aRR 3.79, 95% CI 1.40-10.23) were associated with delayed onset of active labor following vaginal misoprostol administration whereas higher body mass index (aRR 0.38, 95% CI 0.18-0.79) decreased the risk.

CONCLUSION

Delayed onset of active labor following labor induction remains an important obstetric care challenge. Mothers undergoing labor induction should have their body mass index documented, and nulliparous women and mothers at less than 37 weeks of gestation should have their labor monitored for a longer duration following labor induction.

Oral or Vaginal Misoprostol for Labor Induction and Cesarean Delivery Risk

OBJECTIVE

To evaluate whether cervical ripening with oral misoprostol increases cesarean delivery risk and prolongs time to vaginal delivery compared with vaginal misoprostol in a predominantly overweight population.

METHODS

This single center, retrospective cohort study was performed at a tertiary care academic medical center and compared labor induction outcomes with vaginal misoprostol to outcomes with oral misoprostol after a complete institutional shift to oral misoprostol. Labor induction using 25 micrograms vaginal misoprostol in 2013-2014 was compared with 50 micrograms oral misoprostol in 2014-2015. The primary outcome was cesarean delivery. Secondary outcomes included time to vaginal delivery, uterine tachysystole, maternal hemorrhage, and composite adverse neonatal outcomes. Demographics and outcomes were analyzed using standard statistical tests. Multivariable regression models accounting for potential confounders were created for the primary and secondary outcomes with adjusted odds ratios (aOR) as the measures of effect.

RESULTS

There were 138 women in the oral and 138 women in the vaginal misoprostol groups. In the overall cohort, the median (interquartile range) body mass index was 31.7 (28.2-36.8) and most women (72%) were of either black or Hispanic race or ethnicity. The frequency of cesarean delivery was higher in the oral than the vaginal misoprostol group (32% vs 21%; P=.04). The adjusted odds of cesarean was higher with oral misoprostol (aOR 2.01; 95% CI 1.07-3.76). Among nulliparous women, the frequency of cesarean delivery was 41% in the oral and 28% in the vaginal misoprostol groups (aOR 2.79; 95% CI 1.26-6.19). Women had a longer time to vaginal delivery in the oral compared with vaginal misoprostol group (41 vs 31 hours respectively, P=.01). Tachysystole occurred more frequently with vaginal misoprostol (20% vs 11%; P=.04).

CONCLUSION

Compared with vaginal misoprostol, oral misoprostol may be associated with increased risk of cesarean delivery and longer time to vaginal delivery.

Which method is best for the induction of labour? A systematic review, network meta-analysis and cost-effectiveness analysis

BACKGROUND

More than 150,000 pregnant women in England and Wales have their labour induced each year. Multiple pharmacological, mechanical and complementary methods are available to induce labour.

OBJECTIVE

To assess the relative effectiveness, safety and cost-effectiveness of labour induction methods and, data permitting, effects in different clinical subgroups.

METHODS

We carried out a systematic review using Cochrane methods. The Cochrane Pregnancy and Childbirth Group's Trials Register was searched (March 2014). This contains over 22,000 reports of controlled trials (published from 1923 onwards) retrieved from weekly searches of OVID MEDLINE (1966 to current); Cochrane Central Register of Controlled Trials (The Cochrane Library); EMBASE (1982 to current); Cumulative Index to Nursing and Allied Health Literature (1984 to current); ClinicalTrials.gov; the World Health Organization International Clinical Trials Registry Portal; and hand-searching of relevant conference proceedings and journals. We included randomised controlled trials examining interventions to induce labour compared with placebo, no treatment or other interventions in women eligible for third-trimester induction. We included outcomes relating to efficacy, safety and acceptability to women. In addition, for the economic analysis we searched the Database of Abstracts of Reviews of Effects, and Economic Evaluations Databases, NHS Economic Evaluation Database and the Health Technology Assessment database. We carried out a network meta-analysis (NMA) using all of the available evidence, both direct and indirect, to produce estimates of the relative effects of each treatment compared with others in a network. We developed a de novo decision tree model to estimate the cost-effectiveness of various methods. The costs included were the intervention and other hospital costs incurred (price year 2012-13). We reviewed the literature to identify preference-based utilities for the health-related outcomes in the model. We calculated incremental cost-effectiveness ratios, expected costs, utilities and net benefit. We represent uncertainty in the optimal intervention using cost-effectiveness acceptability curves.

RESULTS

We identified 1190 studies; 611 were eligible for inclusion. The interventions most likely to achieve vaginal delivery (VD) within 24 hours were intravenous oxytocin with amniotomy [posterior rank 2; 95% credible intervals (CrIs) 1 to 9] and higher-dose (≥ 50 µg) vaginal misoprostol (rank 3; 95% CrI 1 to 6). Compared with placebo, several treatments reduced the odds of caesarean section, but we observed considerable uncertainty in treatment rankings. For uterine hyperstimulation, double-balloon catheter had the highest probability of being among the best three treatments, whereas vaginal misoprostol (≥ 50 µg) was most likely to increase the odds of excessive uterine activity. For other safety outcomes there were insufficient data or there was too much uncertainty to identify which treatments performed 'best'. Few studies collected information on women's views. Owing to incomplete reporting of the VD within 24 hours outcome, the cost-effectiveness analysis could compare only 20 interventions. The analysis suggested that most interventions have similar utility and differ mainly in cost. With a caveat of considerable uncertainty, titrated (low-dose) misoprostol solution and buccal/sublingual misoprostol had the highest likelihood of being cost-effective.

LIMITATIONS

There was considerable uncertainty in findings and there were insufficient data for some planned subgroup analyses.

CONCLUSIONS

Overall, misoprostol and oxytocin with amniotomy (for women with favourable cervix) is more successful than other agents in achieving VD within 24 hours. The ranking according to safety of different methods was less clear. The cost-effectiveness analysis suggested that titrated (low-dose) oral misoprostol solution resulted in the highest utility, whereas buccal/sublingual misoprostol had the lowest cost. There was a high degree of uncertainty as to the most cost-effective intervention.

FUTURE WORK

Future trials should be powered to detect a method that is more cost-effective than misoprostol solution and report outcomes included in this NMA.

STUDY REGISTRATION

This study is registered as PROSPERO CRD42013005116.

FUNDING

The National Institute for Health Research Health Technology Assessment programme.

Avoiding Medical Induction With Electrostimulation Acupuncture: A Private Practice Case Series of 8 Pregnant Women

Eight pregnant women and their private practice obstetricians sought acupuncture as an alternative to the risks of medical induction. This retrospective case series attempts to show that electroacupuncture-induced labor is a low-risk and feasible approach to getting labor started for women who may be at term or just past their due date and want to avoid medical induction. All 8 women went into labor following acupuncture treatments, suggesting feasibility for electrostimulation acupuncture as a method to induce labor within 24 h or less of 1 treatment.

Comparison of Vaginal and Oral Doses of Misoprostol for Labour Induction in Post-Term Pregnancies

INTRODUCTION

Considering maternal complications, it is preferred to induce labour after 40 weeks. Labour induction is a procedure used to stimulate uterine contractions during pregnancy before the beginning of the labour.

AIM

The aim of this study was to compare oral misoprostol with vaginal misoprostol for induction of labour in post-term pregnancies.

MATERIALS AND METHODS

This double blind clinical-trial study was performed on 180 post-term pregnant women who were admitted to the labour ward of Besat Hospital Sanandaj, Iran in 2013-2014. Participants were equally divided into three groups using block randomization method. The induction was performed for the first group with 100 μg of oral misoprostol, for the second group with 50 μg of oral misoprostol, and for the third group with 25 μg of vaginal misoprostol. Vaginal examination and FHR was done before repeating each dose to determine Bishop Score. Induction time with misoprostol to the start of uterine contractions, induction time to delivery, and mode of delivery, systolic tachycardia, hyper stimulation and fetal outcomes were studied as well.

RESULTS

First minute Apgar scores and medication dosage of the study groups were significantly different (p=0.0001). But labour induction, induction frequency, mode of delivery, complications, and 5 minutes Apgar score in the groups had no significant difference (p>0.05). The risk of fetal distress and neonatal hospitalization of the groups were statistically significant (p=0. 02). There was no significant difference between the three groups in terms of mean time interval from the administration of misoprostol to the start of uterine contractions (labour induction), the time interval from the start of uterine contractions to delivery and taking misoprostol to delivery. From the administration of misoprostol to start of the uterine contractions the mean difference between time intervals in the three groups were not statistically significant.

CONCLUSION

Based on our findings it can be concluded that prescribing 100μg oral misoprostol is effective than 50 μg oral or 25 μg vaginal misoprostol in terms of induction time, maternal and neonatal outcomes in post- term pregnancy. However, the best dose and route should be decided according to evidence based information.

Sublingual Misoprostol (PGE1) Versus Intracervical Dinoprostone (PGE2) Gel for Induction of Labour: A Randomized Control Trail

BACKGROUND

Prostaglandins are popular agents for induction of labour, owing to their dual action of cervical ripening and inducing uterine contractions. Sublingual misoprostol offers high efficacy as it bypasses first-pass metabolism. Researchers have proved that intracervical PGE1 is as effective as PGE2 except for increased caesarean rate and hyperstimulation. Limited knowledge is available on the efficacy of sublingual PGE1 and intracervical PGE2. This study was designed to compare the effectiveness of sublingual PGE1 with intracervical PGE2.

METHODS

A randomized control trial was conducted in Bangalore Baptist Hospital, Bangalore. One hundred and ninety women with singleton, term pregnancy were equally divided into PGE1 and PGE2 groups, and primary outcome was measured.

RESULTS

Post-induction mean Bishop's score in PGE1 group was statistically significant (t = 6.57, p < 0.05). Failed induction rate (1 vs 13.6 %) and need for augmentation (46.3 vs 62.1 %) were lower with PGE1 than those with PGE2 (p < 0.05). Significant (p < 0.05) maternal and foetal outcomes like higher rate of NVD (35.8 vs 26 %), lower LSCS rate (15.8 vs 32.6 %), lower incidence of foetal complications (7.3 vs 21 %) were noted with PGE1. APGAR scores at 1 and 5 min were not significant. Mean cost of induction with PGE1 was 12.55+/4.15 INR and with PGE2 470.65+/126.5.

CONCLUSION

Sublingual PGE1 is a better cervical ripening agent, faster and more effective, with a shorter induction-to-delivery interval as compared to intracervical PGE2. We also noted lower incidence of caesarean section and foetal distress with sublingual PGE1 compared to oral or vaginally administered PGE1.

Oral misoprostol for induction of labour

BACKGROUND

Misoprostol is an orally active prostaglandin. In most countries misoprostol is not licensed for labour induction, but its use is common because it is cheap and heat stable.

OBJECTIVES

To assess the use of oral misoprostol for labour induction in women with a viable fetus.

SEARCH METHODS

We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (17 January 2014).

SELECTION CRITERIA

Randomised trials comparing oral misoprostol versus placebo or other methods, given to women with a viable fetus for labour induction.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed trial data, using centrally-designed data sheets.

MAIN RESULTS

Overall there were 76 trials (14,412) women) which were of mixed quality.In nine trials comparing oral misoprostol with placebo (1109 women), women using oral misoprostol were more likely to give birth vaginally within 24 hours (risk ratio (RR) 0.16, 95% confidence interval (CI) 0.05 to 0.49; one trial; 96 women), need less oxytocin (RR 0.42, 95% CI 0.37 to 0.49; seven trials; 933 women) and have a lower caesarean section rate (RR 0.72, 95% CI 0.54 to 0.95; eight trials; 1029 women).In 12 trials comparing oral misoprostol with vaginal dinoprostone (3859 women), women given oral misoprostol were less likely to need a caesarean section (RR 0.88, 95% CI 0.78 to 0.99; 11 trials; 3592 women). There was some evidence that they had slower inductions, but there were no other statistically significant differences.Nine trials (1282 women) compared oral misoprostol with intravenous oxytocin. The caesarean section rate was significantly lower in women who received oral misoprostol (RR 0.77, 95% CI 0.60 to 0.98; nine trials; 1282 women), but they had increased rates of meconium-stained liquor (RR 1.65, 95% CI 1.04 to 2.60; seven trials; 1172 women).Thirty-seven trials (6417 women) compared oral and vaginal misoprostol and found no statistically significant difference in the primary outcomes of serious neonatal morbidity/death or serious maternal morbidity or death. The results for vaginal birth not achieved in 24 hours, uterine hyperstimulation with fetal heart rate (FHR) changes, and caesarean section were highly heterogenous - for uterine hyperstimulation with FHR changes this was related to dosage with lower rates in those with lower doses of oral misoprostol. However, there were fewer babies born with a low Apgar score in the oral group (RR 0.60, 95% CI 0.44 to 0.82; 19 trials; 4009 babies) and a decrease in postpartum haemorrhage (RR 0.57, 95% CI 0.34 to 0.95; 10 trials; 1478 women). However, the oral misoprostol group had an increase in meconium-stained liquor (RR 1.22, 95% CI 1.03 to 1.44; 24 trials; 3634 women).

AUTHORS' CONCLUSIONS

Oral misoprostol as an induction agent is effective at achieving vaginal birth. It is more effective than placebo, as effective as vaginal misoprostol and results in fewer caesarean sections than vaginal dinoprostone or oxytocin.Where misoprostol remains unlicensed for the induction of labour, many practitioners will prefer to use a licensed product like dinoprostone. If using oral misoprostol, the evidence suggests that the dose should be 20 to 25 mcg in solution. Given that safety is the primary concern, the evidence supports the use of oral regimens over vaginal regimens. This is especially important in situations where the risk of ascending infection is high and the lack of staff means that women cannot be intensely monitored.