Titrated oral misoprostol solution for induction of labour: a multi-centre, randomised trial

Oral misoprostol alone, compared with oral misoprostol followed by oxytocin, in women induced for hypertension of pregnancy: A multicentre randomised trial

OBJECTIVE

To assess whether, in those requiring continuing uterine stimulation after cervical ripening with oral misoprostol and membrane rupture, augmentation with low-dose oral misoprostol is superior to intravenous oxytocin.

DESIGN

Open-label, superiority randomised trial.

SETTING

Government hospitals in India.

POPULATION

Women who were induced for hypertensive disease in pregnancy and had undergone cervical ripening with oral misoprostol, but required continuing stimulation after artificial membrane rupture.

METHODS

Participants received misoprostol (25 micrograms, orally, 2-hourly) or titrated oxytocin through an infusion pump. All women had one-to-one care; fetal monitoring was conducted using a mixture of intermittent and continuous electronic fetal monitoring.

MAIN OUTCOME MEASURES

Caesarean birth.

RESULTS

A total of 520 women were randomised and the baseline characteristics were comparable between the groups. The caesarean section rate was not reduced with the use of misoprostol (misoprostol, 84/260, 32.3%, vs oxytocin, 71/260, 27.3%; aOR 1.23; 95% CI 0.81-1.85; P = 0.33). The interval from randomisation to birth was somewhat longer with misoprostol (225 min, 207-244 min, vs 194 min, 179-210 min; aOR 1.137; 95% CI 1.023-1.264; P = 0.017). There were no cases of hyperstimulation in either arm. The rates of fetal heart rate abnormalities and maternal side effects were similar. Fewer babies in the misoprostol arm were admitted to the special care unit (10 vs 21 in the oxytocin group; aOR 0.463; 95% CI 0.203-1.058; P = 0.068) and there were no neonatal deaths in the misoprostol group, compared with three neonatal deaths in the oxytocin arm. Women's acceptability ratings were high in both study groups.

CONCLUSIONS

Following cervical preparation with oral misoprostol and membrane rupture, the use of continuing oral misoprostol for augmentation did not significantly reduce caesarean rates, compared with the use of oxytocin. There were no hyperstimulation or significant adverse events in either arm of the trial.

Sublingual misoprostol vs. oral misoprostol solution for induction of labor: A retrospective study

Introduction

Induction of labor (IOL) is one of the most common obstetrical procedures, with an increasing rate. The prostaglandin E1 analogue misoprostol is frequently used as a primary method of labor induction. The optimal dose and route of administration is yet to be ascertained.

Aim

To compare efficiacy and safety between a regimen of sublingually administered misoprostol and a regimen of orally administered misoprostol, with cesarean delivery as primary outcome.

Methods

A retrospective study was conducted including women carrying a live, singleton fetus in a cephalic position with labor induced at >37 + 0 gestational weeks at Skåne University hospital, Lund, between January 1st 2013 to December 31st 2017. Data was obtained from computerized obstetrical charts.

Results

Totally 2,404 women were included; 974 induced with sublingual misoprostol and 1,430 with oral solution. In primiparous women the cesarean delivery rate was lower in primiparous women induced with oral compared to sublingual misoprostol (20.5% vs. 28.6%, p < 0.001), whereas in parous women the rates did not differ significantly 4.9% vs. 7.5%; NS). The increased risk of caesarean remained after controlling for potential confounding factors (adjusted odds ratio 1.49 (1.14–1.95). Women induced with sublingual misoprostol had a shorter time to vaginal delivery when compared to oral solution (primiparous median 16.7 h vs. 21.7 h; p < 0.001, parous median 9.9 h vs. 13.3 h; p = 0.01), and a higher rate of vaginal delivery within 24 h (primiparas 77.7% vs. 63.3%, p < 0.001, parous 93.2% vs. 84.2%; p = 0.01).

Conclusion

IOL with oral misoprostol solution was associated with a significantly higher vaginal delivery rate when compared to sublingual misoprostol, whereas sublingual misoprostol was associated with a significantly shorter time from induction to vaginal delivery. Oral administration is considered the most safe and efficient administration of misoprostol, although more studies are needed to find the optimal route and dosage of misoprostol for IOL.

Oral Misoprostol alone versus oral misoprostol followed by oxytocin for labour induction in women with hypertension in pregnancy (MOLI): protocol for a randomised controlled trial

BACKGROUND

Every year approximately 30,000 women die from hypertensive disease in pregnancy. Magnesium sulphate and anti-hypertensives reduce morbidity, but delivery is the only cure. Low dose oral misoprostol, a prostaglandin E1 analogue, is a highly effective method for labour induction. Usually, once active labour has commenced, the misoprostol is replaced with an intravenous oxytocin infusion if ongoing stimulation is required. However, some studies have shown that oral misoprostol can be continued into active labour, a simpler and potentially more acceptable protocol for women. To date, these two protocols have never been directly compared.

METHODS

This pragmatic, open-label, randomised trial will compare a misoprostol alone labour induction protocol with the standard misoprostol plus oxytocin protocol in three Indian hospitals. The study will recruit 520 pregnant women being induced for hypertensive disease in pregnancy and requiring augmentation after membrane rupture. Participants will be randomised to receive either further oral misoprostol 25mcg every 2 h, or titrated intravenous oxytocin. The primary outcome will be caesarean birth. Secondary outcomes will assess the efficacy of the induction process, maternal and fetal/neonatal complications and patient acceptability. This protocol (version 1.04) adheres to the SPIRIT checklist. A cost-effectiveness analysis, situational analysis and formal qualitative assessment of women's experience are also planned.

DISCUSSION

Avoiding oxytocin and continuing low dose misoprostol into active labour may have a number of benefits for both women and the health care system. Misoprostol is heat stable, oral medication and thus easy to store, transport and administer; qualities particularly desirable in low resource settings. An oral medication protocol requires less equipment (e.g. electronic infusion pumps) and may free up health care providers to assist with other aspects of the woman's care. The simplicity of the protocol may also help to reduce human errors associated with the delivery of intravenous infusions. Finally, women may prefer to be mobile during labour and not restricted by an intravenous infusion. There is a need, therefore, to assess whether augmentation using oral misoprostol is superior clinically and economically to the standard protocol of intravenous oxytocin.

TRIAL REGISTRATION

Clinical Trials.gov, NCT03749902 , registered on 21^st Nov 2018.

Prevalence of uterine rupture among women with one prior low transverse cesarean and women with unscarred uterus undergoing labor induction with PGE2: A systematic review and meta-analysis

BACKGROUND

As uterine rupture may affect as many as 11/1000 women with 1 prior cesarean birth and 5/10.000 women with unscarred uterus undergoing labor induction, we intended to estimate the prevalence of such rare outcome when PGE2 is used for cervical ripening and labor induction.

METHODS

We searched MEDLINE, ClinicalTrials.gov and the Cochrane library up to September 1st 2020. Retrospective and prospective cohort studies, as well as randomized controlled trials (RCTs) on singleton viable pregnancies receiving PGE2 for cervical ripening and labor induction were reviewed. Prevalence of uterine rupture was meta-analyzed with Freeman-Tukey double arcsine transformation among women with 1 prior low transverse cesarean section and women with unscarred uterus.

RESULTS

We reviewed 956 full text articles to include 69 studies. The pooled prevalence rate of uterine rupture is estimated to range between 2 and 9 out of 1000 women with 1 prior low transverse cesarean (5/1000; 95%CI 2-9/1000, 122/9000). The prevalence of uterine rupture among women with unscarred uterus is extremely low, reaching at most 0.7/100.000 (<1/100.000.000; 95%CI <1/100.000.000-0.7/100.000, 8/17.684).

CONCLUSIONS

Uterine rupture is a rare event during cervical ripening and labor induction with PGE2.

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.

Women's expectations and experiences of labor induction - a questionnaire-based analysis of a randomized controlled trial

BACKGROUND

Although labor induction is a commonly used procedure in obstetrical care, there are limited data on its psycho-emotional effects on the woman. This study analysed the expectations and experiences of women in different routes of labor induction. The study's primary aim was to compare women's delivery experience if induced by orally administrated misoprostol (OMS) compared with misoprostol vaginal insert (MVI). Secondly, an evaluation of women's general satisfaction with induced labor was made, and factors associated with a negative experience.

METHODS

Primiparous women (n = 196) with a singleton fetus in cephalic presentation, ≥ 37 weeks of gestation, with a Bishop's score ≤ 4 planning labor induction were randomly allocated to receive either OMS (Cytotec®) or MVI (Misodel®). Data were collected by validated questionnaires, the Wijma Delivery Expectation/Experience Questionnaire (A + B). The pre-labor part of the survey (W-DEQ version A) was given to participants to complete within 1 hour before the start of induction, and the post-labor part of the questionnaire (W-DEQ version B) was administered after birth and collected before the women were discharged from hospital.

RESULTS

It was found that 11.8% (17/143) reported a severe fear of childbirth (W-DEQ A score ≥ 85). Before the induction, women with extreme fear had 3.7 times increased risk of experiencing labor induction negatively (OR 3.7 [95% CI, 1.04-13.41]).

CONCLUSION

No difference was identified between OMS and MVI when delivery experience among women induced to labor was analysed. Severe fear of childbirth before labor was a risk factor for a negative experience of labor induction.

TRIAL REGISTRATION

Clinical trial register number NCT02918110 . Date of registration on May 31, 2016.

Labor induction with prostaglandin E1 versus E2: a comparison of outcomes

OBJECTIVE

To compare the peripartum outcomes when labor is induced with prostaglandins E₁ versus E₂.

METHODOLOGY

The Consortium of Safe Labor database was utilized. Women with non-anomalous singletons >24 weeks gestation undergoing induction were analyzed. The primary endpoint was a composite adverse maternal outcome with a composite adverse neonatal outcome as our secondary outcome.

RESULTS

Of the 228,438 births within the database, 8229 (10.8%) met inclusion criteria with 4703 (55.7%) receiving PGE₁, and 3741 (44.3%), PGE₂. The rate of vaginal delivery was similar between both. Composite adverse maternal outcome, was more likely among the prostaglandin E₁: 7.2% vs. 1.5% (aOR 4.20; 95% CI 3.02-5.85); similar trend observed with composite adverse neonatal outcome rates: 4.6% vs. 1.4% (aOR 1.69; 95% CI 1.14-2.50).

CONCLUSION

Utilization of prostaglandin E₁, compared to E_2, was associated with an increased likelihood of adverse maternal and neonatal outcomes.

Safety and efficacy of titrated oral misoprostol solution versus vaginal dinoprostone for induction of labor: A single-center randomized control trial

Objective

To compare the efficacy and safety of the hourly administration of titrated oral misoprostol solution (OMS) and vaginal dinoprostone for induction of labor.

Methods

Titrated OMS was administrated hourly for induction of labor, starting with a dose of 20 µg and terminating at a dose of 50 µg. The safety and efficacy of OMS were compared with that of vaginal dinoprostone for induction of labor.

Results

From June 2016 to October 2019, 2280 (78.3%) and 2115 (72.9%) women who received titrated OMS and vaginal dinoprostone, respectively, had a vaginal delivery (P = 0.005). Cesarean delivery was performed in 632 (21.7%) and 783 (27.0%) women who received titrated OMS and vaginal dinoprostone, respectively (P = 0.008). Tachysystole with changes in fetal heart rate (FHR) was seen in 104 (3.6%) and 249 (8.6%) women in the OMS and dinoprostone groups, respectively (P = 0.007). The frequency of non‐reassuring FHR was lower in the OMS group compared to the dinoprostone group (P = 0.006).

Conclusion

The titrated OMS has an efficacy comparable to vaginal dinoprostone. Moreover, it causes a lower incidence of cesarean delivery, lower frequency of tachysystole with changes in FHR, and non‐reassuring FHR.

Titrated oral misoprostol has a similar efficacy to dinoprostone, but with a lower incidence of cesarean delivery and lower frequency of non‐reassuring fetal heart rate.

A Relative Bioavailability Study of Two Misoprostol Formulations Following a Single Oral or Sublingual Administration

Introduction

Misoprostol (Cytotec) was primarily made for treating gastric ulcers. However today it is mostly used for abortion, treating postpartum hemorrhage, and for induction of labor. The tablet contains 200 µg of misoprostol, yet the dosages used for induction of labor are much smaller (25–50 µg), leading to uncertainty of dosage in daily use.

Aim

To evaluate and compare the relative bioavailability of two misoprostol products (Angusta 25 µg and Cytotec 200 µg tablets) administered orally or sublingually given in a daily clinical setting to women admitted for induction of labor at term.

Methods

Women carrying a live, singleton fetus in a cephalic position and with a gestational age between 259 and 296 days were included. Blood samples were collected at 0, 5, 10, 20, 30, 40, 50, 75, 100, 120, 180, and 240 minutes. A serum analytical assay was performed and pharmacokinetic parameters were calculated. Patients were assigned to one of three groups.

Results

A total of 72 patients were included. No significant differences demographic characteristics were found. The ratios for AUC, AUC (_0−t), and C_max were similar in all three groups, but CI-values were outside the required 80–125%. Sublingual administration yielded a 20–30% higher bioavailability and a 50% higher C_max than compared to the oral route.

Conclusion

The relative bioavailability between Angusta and Cytotec could not be confirmed as being equal at the 25 µg or 50 µg level because the 90% CI-values when comparing the ratios for AUC, AUC_(0−t), and C_max were wider than accepted. The reason for this could be the real-life, non-standardized circumstances in which the study was conducted. Sublingual administration seems to have higher bioavailability than oral administration. More studies are needed to ascertain an optimal dosage regime balancing both safety and efficacy for mother and child.

Clinical Trial Registration

www.ClinicalTrials.gov, identifier NCT02516631.

Oral Misoprostol Versus Vaginal Prostaglandin E2 Labor Induction Efficiency, Safety, and Labor Outcomes

BACKGROUND

Prostaglandin E1 (oral misoprostol) and the other Prostaglandin E2 (Dinoprostone gel) are promising agents for cervical ripening and induction of labor.

AIMS OF STUDY

To compare the efficiency and safety on maternal-fetal outcomes using 25 micrograms oral misoprostol PGE1 with 50 micrograms of intra-vaginal PGE2 for induction of labor.

METHODS

This was a retrospective study design reviewing medical records of induced labor at Al Shifa hospital in Gaza Strip.

RESULTS

In general, the results showed that women who used oral misoprostol with an age less than 30 years and parity less than 3 was effective for delivery and safe outcomes with an odds ratio (OR) of 15.8 (CI 6.9–39.8) and OR 29.2 (CI 10.7–80.3) respectively. The most common indication for labor induction in both methods was reputure of the membrane (ROM) more than 24 hours, postdates, and a medical disorder. However, the total interval hours for both methods was 8.4 hours. The mode of delivery was similar in both groups as vaginal delivery outcome was 73.6% for oral misoprostol E1 and 75% for prostaglandin E2 cases. However, PGE2 induction showed a higher cesarean delivery 25% rate versus 18.4%. Clinically the use of oral misoprostol showed a higher percentage of birth canal injury, failed induction, uterine rupture by 9.3%, 8%, 1.3% respectively. Fetal distress was found as the most common fetal complication and the most common cause for cesarean section.

CONCLUSION

The study recommended more research is needed as present evidence does not support use of oral misoprostol versus Prostaglandin E2.

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.

[Induction of labour at term with misoprostol: the experience of a Tunisian maternity ward]

To evaluate the efficacy and safety of vaginal misoprostol for term labour induction. A prospective study conducted at the Department of Obstetrics and Gynecology B of hospital Charles Nicolle, Tunis, over a period of 4 months. The group of subjects, selected to represent the population of interest, were pregnant patients at term undergoing cervical ripening. Patients received 50 mcg vaginal misoprostol every 12 hours. The parameters studied were: contractile abnormalities, abnormalities of fetal heart rate (FHR), mode of delivery, delayed delivery and neonatal status. 44 patients underwent cervical ripening with misoprostol. The average term was 40 WA. Nulliparous rate was 23/44 (52%). Vaginal birth rate was 31/44 (70.4%). 84% of patients received a single dose of misoprostol. FHR abnormalities were observed in 14/44 (32%). The rates of meconium-stained amniotic fluid was 12/44 (27%). Apgar score of less than 7 at 5 minutes was found in 7/44 (16%). A case of uterine rupture occurred in a primipara after a single dose of misoprostol. Our results are disappointing due to the occurrence of 1 uterine rupture and of 1 significant neonatal morbidity. Other multicentre prospective studies will be useful to better ensure the effectiveness but primarily the safety of low-dose misoprostol for induction of labour at term.

Comparative study of titrated oral misoprostol solution and vaginal dinoprostone for labor induction at term pregnancy

OBJECTIVE

To evaluate effectiveness and safety of titrated oral misoprostol solution (OMS) in comparison with vaginal dinoprostone for cervix ripening and labor induction in term pregnant women.

METHODS

A multicenter randomized controlled trial of women with term singleton pregnancy with indications for labor induction; 481 participants were allocated to receive titrated OMS with different doses by hourly administration according to the procedure or insert vaginal dinoprostone for cervix ripening and labor induction to compare maternal outcomes including indication of labor induction, mode of outcome of delivery, maternal morbidity, and neonatal outcomes between two groups for evaluating the efficacy and safety of titrated oral misoprostol induction.

RESULT

Proportion of delivery within 12 h of titrated oral misoprostol is significantly less than vaginal dinoprostone (p = 0.03), but no difference of total vaginal delivery rate (p = 0.93); the mean time of first treatment to vaginal delivery was longer in OMS group (21.3 ± 14.5 h) compared with the vaginal dinoprostone group (15.7 ± 9.6 h). Although the proportion of cesarean section between the two groups showed no statistically significant difference, OMS group showed significantly lower frequency of uterine hyperstimulation, hypertonus, partus precipitatus and non-reassuring fetal heart rate than dinoprostone group. Neonatal outcomes were similar evaluating from Apgar score and NICU admission. Our study also showed that labor induction of women with cervix Bishop score ≤3 needed increased dosage of misoprostol solution.

CONCLUSION

Titrated OMS is as effective as vaginal dinoprostone in labor induction for term pregnant women, with safer effect for its lower rate of adverse effect for women.

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.

Oral misoprostol versus vaginal dinoprostone for labor induction in nulliparous women at term

OBJECTIVE

To compare the efficacy of oral misoprostol to vaginal dinoprostone for labor induction in nulliparous women.

STUDY DESIGN

Admissions for labor induction from January 2008 to December 2010 were reviewed. Patients receiving oral misoprostol were compared with those receiving vaginal dinoprostone. The primary outcome was time from induction agent administration to vaginal delivery. Secondary outcomes included vaginal delivery within 24 h, mode of delivery and maternal and fetal outcomes.

RESULT

A total of 680 women were included: 483 (71%) received vaginal dinoprostone and 197 (29%) received oral misoprostol. Women who received oral misoprostol had a shorter interval to vaginal delivery (27.2 vs 21.9 h, P<0.0001) and were more likely to deliver vaginally in <24 h (47% vs 64%, P=0.001). There was no increase in the rate of cesarean delivery or adverse maternal or neonatal outcomes.

CONCLUSION

Labor induction with oral misoprostol resulted in shorter time to vaginal delivery without increased adverse outcomes in nulliparous women.

Individualized misoprostol dosing for labor induction or augmentation: A review

Cesarean birth rates are greater than 20% in many developed countries. The main diagnoses contributing to the high rate of cesarean births in nulliparous women are dystocia and prolonged labor. Traditionally, a policy of vaginal dinoprostone for the treatment of unripe cervix or early amniotomy with oxytocin administration for a ripened cervix has been associated with a modest reduction in the rate of cesarean births due to arrest disorders. However, the course of vaginal dinoprostone is tedious and oxytocin should be administered through an infusion pump, which may be inconvenient in certain settings. Because misoprostol has powerful uterotropic and uterotonic effects, and has become a common agent used in the practice of obstetrics and gynecology, the United States Food and Drug Administration removed the absolute contraindication of the drug during pregnancy from its label in April 2002. However, excessive uterine contractility resulting in tachysystole or fetal distress is always a concern with the oral or vaginal use of fixed-dosage misoprostol. Therefore, misoprostol should be administered with caution to ensure that fetal hypoxia does not occur. A pilot trial examining the use of very small, frequent, titrated oral misoprostol dosages administered every 2 h was first conducted by Hofmeyr et al in 2001. Given women’s different metabolisms and responses to misoprostol, another method of titrating individualized oral misoprostol with dosing administered every hour relative to uterine response was then developed by Cheng in 2006. Based on previous studies, this titration method is potentially an ideal alternative to traditional dinoprostone, oxytocin or the previously established misoprostol dosing method for labor induction or augmentation.

The routine use of oxytocin after oral misoprostol for labour induction in women with an unfavourable cervix is not of benefit

BACKGROUND

Induction of labour with misoprostol is often augmented with oxytocin with the possible consequence of uterine hypercontractility. It is important to determine whether the use of oxytocin in this circumstance has benefit as well as risk.

AIM

To compare two regimens for labour induction in women with an unfavourable cervix: oral misoprostol vs. oral misoprostol routinely followed by oxytocin.

METHODS

A prospective randomised trial in which 200 women with an unfavourable cervix received either oral misoprostol 25 microg every 3 h (group 1, n = 100) or two such doses routinely followed by oxytocin (group 2, n = 100). Outcomes included change in Bishop score, induction delivery interval, oxytocin requirement, contraction abnormalities, mode of delivery and neonatal outcome.

RESULT

The improvement in Bishop score with two misoprostol doses in all 200 women was highly significant (2.9 +/- 1.5 to 6.6 +/- 1.9, P < 0.0001). The induction delivery interval, Caesarean delivery rate, vaginal delivery rate within 24 h, contraction abnormalities and neonatal outcome were similar in both groups. Contraction abnormalities were remarkably low with either regimen (1%). Routine addition of oxytocin 3 h after the second misoprostol dose (group 2) resulted in the maximum oxytocin dose (64 mU/min) being given to more women (66% in group 2; 36% in group 1).

CONCLUSION

There was no benefit of routine addition of oxytocin after two doses of misoprostol. Reduced oxytocin requirement was observed when it was added only if needed. Both regimens achieved 85-87% vaginal deliveries with low incidence of hypercontractility.

Oral misoprostol for induction of labour at term: randomised controlled trial

OBJECTIVE

To compare oral misoprostol solution with vaginal prostaglandin gel (dinoprostone) for induction of labour at term to determine whether misoprostol is superior.

DESIGN

Randomised double blind placebo controlled trial.

SETTING

Maternity departments in three hospitals in Australia. Population Pregnant women with a singleton cephalic presentation at > or = 36+6 weeks' gestation, with an indication for prostaglandin induction of labour.

INTERVENTIONS

20 mug oral misoprostol solution at ourly intervals and placebo vaginal gel or vaginal dinoprostone gel at six hourly intervals and placebo oral solution.

MAIN OUTCOME MEASURES

Vaginal birth within 24 hours; uterine hyperstimulation with associated changes in fetal heart rate; caesarean section (all); and caesarean section for fetal distress.

RESULTS

741 women were randomised, 365 to the misoprostol group and 376 to the vaginal dinoprostone group. There were no significant differences between the two treatment groups in the primary outcomes: vaginal birth not achieved in 24 hours (misoprostol 168/365 (46.0%) v dinoprostone 155/376 (41.2%); relative risk 1.12, 95% confidence interval 0.95 to 1.32; P = 0.134), caesarean section (83/365 (22.7%) v 100/376 (26.6%); 0.82, 0.64 to 1.06; P = 0.127), caesarean section for fetal distress (32/365 (8.8%) v 35/376 (9.3%); 0.91, 0.57 to 1.44; P = 0.679), or uterine hyperstimulation with changes in fetal heart rate (3/365 (0.8%) v 6/376 (1.6%); 0.55, 0.14 to 2.21; P = 0.401). Although there were differences in the process of labour induction, there were no significant differences in adverse maternal or neonatal outcomes.

CONCLUSIONS

This trial shows no evidence that oral misoprostol is superior to vaginal dinoprostone for induction of labour. However, it does not lead to poorer health outcomes for women or their infants, and oral treatment is preferred by women.

TRIAL REGISTRATION

National Health and Medical Research Council, Perinatal Trials, PT0361.

Comparison of misoprostol and dinoprostone for elective induction of labour in nulliparous women at full term: a randomized prospective study

BACKGROUND

The objective of this randomized prospective study was to compare the efficacy of 50 mcg vaginal misoprostol and 3 mg dinoprostone, administered every nine hours for a maximum of three doses, for elective induction of labor in a specific cohort of nulliparous women with an unfavorable cervix and more than 40 weeks of gestation.

MATERIAL AND METHODS

One hundred and sixty-three pregnant women with more than 285 days of gestation were recruited and analyzed. The main outcome measures were time from induction to delivery and incidence of vaginal delivery within 12 and 24 hours. Admission rate to the neonatal intensive care unit within 24 hours post delivery was a secondary outcome.

RESULTS

The induction-delivery interval was significantly lower in the misoprostol group than in the dinoprostone group (11.9 h vs. 15.5 h, p < 0.001). With misoprostol, more women delivered within 12 hours (57.5% vs. 32.5%, p < 0.01) and 24 hours (98.7% vs. 91.4%, p < 0.05), spontaneous rupture of the membranes occurred more frequently (38.8% vs. 20.5%, p < 0.05), there was less need for oxytocin augmentation (65.8% vs. 81.5%, p < 0.05) and fewer additional doses were required (7.5% vs. 22%, p < 0.05). Although not statistically significant, a lower Caesarean section (CS) rate was observed with misoprostol (7.5% vs. 13.3%, p > 0.05) but with the disadvantage of higher abnormal fetal heart rate (FHR) tracings (22.5% vs. 12%, p > 0.05). From the misoprostol group more neonates were admitted to the intensive neonatal unit, than from the dinoprostone group (13.5% vs. 4.8%, p > 0.05). One woman had an unexplained stillbirth following the administration of one dose of dinoprostone.

CONCLUSIONS

Vaginal misoprostol, compared with dinoprostone in the regimens used, is more effective in elective inductions of labor beyond 40 weeks of gestation. Nevertheless, this is at the expense of more abnormal FHR tracings and more admissions to the neonatal unit, indicating that the faster approach is not necessarily the better approach to childbirth.

A randomised trial comparing low dose vaginal misoprostol and dinoprostone for labour induction

OBJECTIVE

To compare vaginal misoprostol with dinoprostone for induction of labour.

DESIGN

Randomised multicentre trial.

SETTING

Labour wards of one university hospital and two teaching hospitals.

POPULATION

Six hundred and eighty-one women with indication for labour induction at >or=36 weeks of gestation, singleton pregnancy and no previous ceasarean section.

METHODS

Misoprostol (25 mcg, hospital-prepared capsule) in the posterior vaginal fornix, every four hours, maximum three times daily or dinoprostone gel (1 mg) every four hours. Oxytocin was administered if necessary.

MAIN OUTCOME MEASURES

Primary: 'adverse neonatal outcome' (5-minute Apgar score <7 and/or umbilical cord pH <7.15). Secondary: labour duration, mode of delivery and patient satisfaction.

RESULTS

Three hundred and forty-one women received misoprostol and 340 dinoprostone. The median induction-delivery interval was longer in the misoprostol group compared with the dinoprostone group (25 versus 19 hours, P= 0.008). The caesarean section rate was lower in the misoprostol group: 16.1%versus 21%, but this difference was not statistically significant RR = 0.8 (95% CI 0.6-1.04). 'Adverse neonatal outcome' was found to be similar in both groups: 21% in the misoprostol and 23% in the dinoprostone groups. Significantly fewer neonates were admitted to NICU in the misoprostol group compared with dinoprostone 19%versus 26% (RR = 0.7, 95% CI 0.5-0.98).

CONCLUSIONS

Misoprostol in this dosing regimen is a safe method of labour induction. NICU admission rates were lower in the misoprostol group. No difference could be detected in patient satisfaction between groups.

Induction of labor: the misoprostol controversy

Misoprostol (Cytotec) is safe and effective for induction of labor, although it is not approved by the Food and Drug Administration (FDA) for use in pregnancy. In August 2000, the manufacturer of misoprostol warned against its use in pregnancy because of its abortifacient properties and cited reports of maternal and fetal deaths when misoprostol was used to induce labor, fueling the misoprostol controversy. More than 45 randomized trials including more than 5400 women have found vaginal misoprostol to be more effective than oxytocin or vaginal prostaglandin E2 at effecting vaginal delivery within 24 hours. Cesarean delivery rates with vaginal misoprostol are lower than with oxytocin alone, but similar to prostaglandin E2. There have been no significant differences in the frequency of serious adverse maternal or neonatal outcomes with low-dose misoprostol compared with oxytocin or prostaglandin E2; however, the relative risk of rare adverse outcomes with misoprostol is unknown. The data suggest that absolute risks are low when misoprostol is used appropriately. We recommend 25 mcg vaginally every 4 to 6 hours for carefully selected patients in closely monitored settings. Whether misoprostol will prove to be the most cost-effective agent for inducing labor in women with an unfavorable cervix remains to be determined.

Oral misoprostol for induction of labour with a viable fetus

BACKGROUND

Misoprostol is a synthetic prostaglandin which has been used to induce labour. Oral use of the drug misoprostol may be convenient, but an overdose could cause uterine hyperstimulation and precipitate labour which may be life-threatening for both mother and fetus.

OBJECTIVES

The objective of this review was to assess the effects of oral misoprostol used for labour induction in women with a viable fetus.

SEARCH STRATEGY

We searched the Cochrane Pregnancy and Childbirth Group trials register and the Cochrane Controlled Trials Register.

SELECTION CRITERIA

Randomised trials of oral misoprostol versus any other method, placebo or no treatment given to women with a viable fetus for induction of labour.

DATA COLLECTION AND ANALYSIS

The selection of trials and data extraction were undertaken by one reviewer and independently checked by two other reviewers.

MAIN RESULTS

Five trials were included. In one placebo trial, oral misoprostol reduced the need for oxytocin infusion and shortened delivery time in women with prelabour rupture of membranes at term. In another trial, compared to vaginal prostaglandins, oral misoprostol reduced the need for oxytocin (relative risk 0.62, 95% confidence interval 0.47 to 0.82). Based on two trials, the caesarean section rate with oral misoprostol was 20. 2% (55/272) compared with 15.5% (42/270) for vaginal prostaglandins (relative risk 1.29, 95% confidence interval 0.90 to 1.86). Different doses (100 micrograms three hourly and 200 micrograms six hourly) were used in the two trials that compared oral with vaginal misoprostol. The caesarean section rate was 21.8% in the oral misoprostol group compared with 13.5% for vaginal misoprostol (relative risk 1.62, 95% confidence interval 0.85 to 3.09). The uterine hyperstimulation rate with oral misoprostol was 37.5% (36/96) compared with 28% (25/89) for vaginal misoprostol (relative risk 1.32, 95% confidence interval 0.86 to 2.04). There was significant heterogeneity between these two trials.

REVIEWER'S CONCLUSIONS

Oral misoprostol may be an effective method for labour induction. However clinically effective oral regimens may have an unacceptably high incidence of uterine hyperstimulation and possibly uterine rupture.