Oral, vaginal and sublingual misoprostol for induction of labor

Do we need a 200 μg misoprostol vaginal insert? A retrospective cohort study comparing the misoprostol vaginal insert to oral misoprostol

AIM

The misoprostol vaginal insert (MVI) was reported to be more effective than dinoprostone but discussed critically because of high rates of fetal heart rate changes due to uterine tachysystole. The aim of this study was to investigate the outcome of induced labor using the MVI compared to off-label orally-administered misoprostol (OM).

METHODS

Retrospective study including a total of 401 patients with singleton pregnancies in whom labor was induced at ≥36 0/7 gestational weeks with MVI (203) or OM (198). Primary outcomes were the time from induction to delivery, vaginal delivery in 24 h and the mode of delivery and the neonatal outcome.

RESULTS

Median time until any delivery was 833 min (645-1278) for MVI and 1076.5 min (698-1686.3) for OM group; 83.7% of the patients in the MVI group gave birth within 24 h versus 63.6% in the OM group. The MVI group needed significantly less pre-delivery oxytocin (29%). Tachysystole (6.4%) and pathological CTG (30.5%) occurred at a significantly higher frequency in the MVI group. The cesarean section rate was significantly higher in the MVI group amounting to 21.7% versus 14.6% in the OM group (P < 0.05). Neonatal outcome did not differ between the groups.

CONCLUSION

The MVI might be an option if you are in need for an approved and faster method to induce labor. Although we observed a significantly higher rate of fetal heart rate changes and cesarean sections in the MVI group this did not affect the neonatal outcome.

Buccal versus Vaginal Misoprostol for Term Induction of Labor: A Retrospective Cohort Study

OBJECTIVE

To compare the efficacy of similar buccal and vaginal misoprostol doses for induction of labor.

STUDY DESIGN

Retrospective chart review of 207 consecutive women undergoing term induction of labor with misoprostol. Misoprostol route and dosing were collected. Time to delivery and other labor outcomes (e.g., vaginal delivery less than 24 hours) were compared between women receiving buccal and vaginal misoprostol.

RESULTS

There was no significant difference in time to delivery for women receiving buccal (median 18.2 hour, 95% confidence interval [CI] = [14.9, 21.5]) versus vaginal (median 18.3 hour, 95% CI = [15.0, 20.4]) misoprostol (p = 0.428); even after adjusting for covariates (p = 0.381). Women who presented with premature rupture of membranes were more likely to receive buccal misoprostol (92.7% received buccal vs. 7.3% received vaginal, p < 0.001). A similar number of women delivered vaginally in the buccal group (88.2%) and vaginal misoprostol group (86.8%, p = 0.835). The proportion of women who experienced uterine tachysystole or chorioamnionitis did not significantly differ by route of administration.

CONCLUSION

We found no significant differences in time to delivery or other labor outcomes between buccal or vaginal dosing of misoprostol in women undergoing labor induction at term.

Induction to delivery interval using transcervical Foley catheter plus oxytocin and vaginal misoprostol: A comparative study at Aminu Kano Teaching Hospital, Kano, Nigeria

Background:

Induction of labor (IOL) is an artificial initiation of labor before its spontaneous onset for the purpose of delivery of the fetoplacental unit. Many factors are associated with its success in postdatism.

Objective:

To compare the induction delivery intervals using transcervical Foley catheter plus oxytocin and vaginal misoprostol, and to identify the factors associated with successful induction among postdate singleton multiparae.

Materials and Methods:

The study was a prospective randomized controlled trial of singleton multiparous pregnant women. They were randomized into two groups, one group for intravaginal misoprostol and the other group for transcervical Foley catheter insertion as a method of cervical ripening and IOL. The data were analyzed using SPSS version 17 computer software (SPSS Inc., IL, Chicago, USA). Comparisons of categorical variables were done using Chi-squared test, with P < 0.05 considered as significant. Student's t-test was used for continuous variables.

Results:

The incidence of postdatism was found to be 136 (13.1%). The mean induction delivery time interval was shorter in the misoprostol group 70 (5.54 ± 1.8 h) than in the Foley catheter oxytocin infusion group 66 (6.65 ± 1.7 h) (P = 0.035). There was, however, no statistically significant difference in the maternal and neonatal outcomes when these two agents were used for cervical ripening and IOL. Higher parity and higher Bishop's score were the factors found to be associated with high success rate of IOL (P < 0.001).

Conclusion:

Vaginal misoprostol resulted in shorter induction delivery time interval as compared to transcervical Foley catheter. High parity and high Bishop's scores were the factors found to be associated with the success of IOL.

Comparison of the efficacy and safety of sublingual misoprostol with that of vaginal misoprostol for labour induction at term

OBJECTIVE

To compare the efficacy and safety of 50 mcg of sublingual misoprostol with 25 mcg of vaginal misoprostol for induction of labour at term.

METHOD

Non blinded randomized prospective control study. 200 women with singleton term pregnancy, admitted for induction of labour, were randomized to receive either 25 mcg of vaginal misoprostol or 50 mcg of sublingual misoprostol. Outcome measures compared were the number of vaginal deliveries, induction-delivery interval, caesarean section for foetal distress, oxytocin for acceleration, number of doses required, side effects and neonatal outcome.

RESULT

Mean dose was smaller and induction to delivery interval was significantly shorter in the sublingual group (13.1 ± 4.1 h) compared with the vaginal group (17.9 ± 5.4 h), p value 0.001. There were no statistically significant differences in the other secondary outcome measures.

CONCLUSION

50 mcg of sublingual misoprostol was more effective than and as safe as 25 mcg vaginal misoprostol for labour induction at term.

Comparative study of efficacy and safety of oral versus vaginal misoprostol for induction or labour

OBJECTIVE

To compare the efficacy of oral with vaginal misoprostol for induction of labour.

DESIGN

A randomized trial.

SETTING

Tertiary care hospital.

PARTICIPANTS

Two hundred women requiring induction of labour.

METHODS

Group A received oral misoprostol 50 mcg 6 hourly maximum 4 doses to 100 patients and Group B received vaginal misoprostol 50 mcg 6 hourly maximum 4 doses to 100 patients. When the patient entered active stage of labour i.e. clinically adequate constractions of 3/10 min of >40 s duration, and cervical dilatation of with 4 cm, further doses of misoprostol were not administered. Statistical analysis was done using chi-square test and t test.

RESULT

Both groups were comparable with respect to maternal age, gestational age, indication of induction and initial modified Bishops score Mean number of dosage required for successful induction were significantly less in vaginal group than oral group (in oral groups A were 2.73 + 0.58, and in vaginal Group B 2.26 + 0.52, P value < 0.0001 highly significant). The induction delivery interval was significantly less in vaginal group than oral group (Group A 15.24 + 3.47 h Group B 12.74 + 2.60 h, P < 0.0001 highly significant). Oxytocin augmentation required was less in vaginal group. 26 caesarean sections were performed in oral group and 17 caesarean sections were done in vaginal group (P value 0.06 NS). APGAR score, birth weight, NICU admissions showed no difference between the two groups.

CONCLUSION

This study shows that vaginal route of administration of misoprostol is preferable to oral route for induction of labour when used in equivalent dosage of 50 mcg 6 hourly.

Methods of induction of labour: a systematic review

BACKGROUND

Rates of labour induction are increasing. We conducted this systematic review to assess the evidence supporting use of each method of labour induction.

METHODS

We listed methods of labour induction then reviewed the evidence supporting each. We searched MEDLINE and the Cochrane Library between 1980 and November 2010 using multiple terms and combinations, including labor, induced/or induction of labor, prostaglandin or prostaglandins, misoprostol, Cytotec, 16,16,-dimethylprostaglandin E2 or E2, dinoprostone; Prepidil, Cervidil, Dinoprost, Carboprost or hemabate; prostin, oxytocin, misoprostol, membrane sweeping or membrane stripping, amniotomy, balloon catheter or Foley catheter, hygroscopic dilators, laminaria, dilapan, saline injection, nipple stimulation, intercourse, acupuncture, castor oil, herbs. We performed a best evidence review of the literature supporting each method. We identified 2048 abstracts and reviewed 283 full text articles. We preferentially included high quality systematic reviews or large randomised trials. Where no such studies existed, we included the best evidence available from smaller randomised or quasi-randomised trials.

RESULTS

We included 46 full text articles. We assigned a quality rating to each included article and a strength of evidence rating to each body of literature. Prostaglandin E2 (PGE2) and vaginal misoprostol were more effective than oxytocin in bringing about vaginal delivery within 24 hours but were associated with more uterine hyperstimulation. Mechanical methods reduced uterine hyperstimulation compared with PGE2 and misoprostol, but increased maternal and neonatal infectious morbidity compared with other methods. Membrane sweeping reduced post-term gestations. Most included studies were too small to evaluate risk for rare adverse outcomes.

CONCLUSIONS

Research is needed to determine benefits and harms of many induction methods.

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.

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.

Comparison of self-administered vaginal misoprostol versus placebo for cervical ripening prior to operative hysteroscopy using a sequential trial design*

OBJECTIVE

To compare the impact of 1000-microgram self-administered vaginal misoprostol versus self-administered vaginal placebo at home on preoperative cervical ripening in both premenopausal and postmenopausal women prior to outpatient resectoscopy.

DESIGN

Randomised, double-blind, placebo-controlled sequential trial.

SETTING

Norwegian university teaching hospital.

SAMPLE

Premenopausal and postmenopausal women referred to outpatient resectoscopy.

METHODS

The women were randomised to either 1000 micrograms of self-administered vaginal misoprostol or self-administered vaginal placebo the evening before outpatient resectoscopy.

MAIN OUTCOME MEASURES

Preoperative cervical dilatation, acceptability and complications.

RESULTS

(a) Intraoperative findings and distribution of cervical dilatation in the two treatment groups. Values are given as median (range) or n (%). (b) Acceptability in the two treatment groups. Values are given as completely acceptable, n (%); fairly acceptable, n (%); fairly unacceptable, n (%) and completely unacceptable, n (%). (c) Pain in the two treatment groups. Pain was measured with a visual analogue scale score, scale ranges from 0 (no pain) to 10 (unbearable pain). Values are given as median (range). (d) Occurrence of adverse effects in the two treatment groups. Values are given as n (%). (e) Complications, given as n (%).

Sublingual compared with vaginal misoprostol for labour induction at term: a randomised controlled trial

OBJECTIVE

To compare the efficacy and safety of 50 microg of sublingual misoprostol with 25 microg of vaginal misoprostol administered for labour induction at term. Design Double-blinded, randomised controlled trial. Setting University Hospital, Kaunas, Lithuania. Sample A total of 140 women at term with indications for labour induction. Methods Women were randomised to receive either 50 microg of sublingual misoprostol with vaginal placebo (n = 70) or sublingual placebo with 25 microg of vaginal misoprostol (n = 70) every 4 hours (maximum six doses). Main outcome measures The number of women delivering vaginally within 24 hours of labour induction. Results Fifty-eight women (83%) in the sublingual misoprostol group and 53 (76%) in the vaginal misoprostol group delivered vaginally within 24 hours [relative risk (RR) 1.1, 95% confidential interval (CI) 0.9-1.3]. However, the induction to vaginal delivery time was significantly shorter in the sublingual group (15.0 +/- 3.7 hours) compared with the vaginal group (16.7 +/- 4.1 hours, P = 0.03). The incidence of tachysystole was more than three-fold higher in the sublingual than in the vaginal group (14 versus 4.3%; RR 3.3, 95% CI 0.9-11.6), but this was not statistically significant. There were no significant differences in the incidence of hypertonus or hyperstimulation syndrome, mode of delivery, interventions for fetal distress or neonatal outcomes between the two groups. Conclusion A 50 microg of sublingual misoprostol 4 hourly for labour induction at term seems to have similar efficacy as 25 microg of vaginal misoprostol. Further studies on safety with larger numbers of women need to be conducted before routine sublingual misoprostol use in this setting.

Gels as vaginal drug delivery systems

The vagina has been used as a mucosal drug delivery route for a long time. Its single characteristics can be either limitative or advantageous when drug delivery is considered. Gels are semi-solid, three-dimensional, polymeric matrices comprising small amounts of solid, dispersed in relatively large amounts of liquid, yet possessing more solid-like character. These systems have been used and are receiving a great deal of interest as vaginal drug delivery systems. Gels are versatile and have been used as delivery systems for microbicides, contraceptives, labour inducers, and other substances. Although somewhat neglected in clinical studies, pharmaceutical characterization of vaginal gels is an important step in order to optimize safety, efficacy and acceptability. Indeed, the simple formulation of a gel can lead to different performances of systems containing the same amount of active substances. Therefore, this paper discusses and summarizes current use and research of vaginal drug delivery systems based in gels.