The effectiveness of sublingual or oral administration of misoprostol for cervical ripening before manual vacuum aspiration in first trimester termination of pregnancy: randomized controlled trial

OBJECTIVE

To compare the effectiveness of misoprostol sublingual and oral routes before manual vacuum aspiration (MVA) in first trimester termination of pregnancy.

MATERIAL AND METHOD

A double-blinded randomized controlled trial was conducted infirst trimester termination ofpregnancy cases. Eighty cases were recruited and divided into sublingual and oral groups. Both groups were randomized to receive 400 microg misoprostol two hours prior to MVA. Main outcomes were cervical dilatation, operative time, complications, side effects, pain scores, and patient satisfactions.

RESULTS

Sublingual group had significantly more cervical dilatation and shorter operative time than oral group (7.3 +/- 1.5 vs. 5.9 +/- 1.4 mm, p<0.001 and 5.2 +/- 3.3 vs. 7.3 +/- 4.6 min, p = 0.02, respectively). However there were similar side effects, pain scores, and patient satisfactions in two groups. The present study had no uterine perforation, cervical tear hemorrhage, or re-evacuation.

CONCLUSION

Sublingual misoprostol route was more effective for cervical priming prior to MVA in first trimester therapeutic abortion than oral route.

[Clinical analysis of double-balloon catheter for cervical ripening in 66 cases]

OBJECTIVE

To evaluate the efficacy and safety for cervical ripening by double-balloon catheter among full-term pregnancy women underwent labor induction.

METHODS

It was a prospective non-randomly controlled research. Totally 128 singleton-pregnancy women in full-term who had to undergo labor induction because of pregnancy complications or comorbidities from August 2011 to April 2013 in Peking University First Hospital were selected as study subjects. Participants were allocated to preinduction cervical ripening with either a double-balloon catheter (66 participants, study group) or prostaglandin vaginal insert (62 participants, control group). Compare the efficacy for cervical ripening and adverse reactions between the two groups.

RESULTS

The efficacy for cervical ripening (Bishop scores improved by ≥ 2) had no significant differences between study and control groups [82% (54/66) compared with 81% (50/62), P > 0.05]. The time interval between intervention and parturiency was significantly higher in the double balloon catheter group than in the prostaglandin vaginal insert group [(24.2 ± 8.5) compared with (14.5 ± 8.0) hours, P < 0.05]. The proportion of women who achieved parturiency within 12 hours was significantly lower in the double-balloon catheter group than that in the control group [9% (6/66) compared with 21% (13/62), P < 0.05]. The cesarean section rate showed no significant differences [41% (27/66) compared with 43% (27/62), P > 0.05]. The prevalence of intrauterine infection demonstrated by clinical diagnosis was significantly higher in the double- balloon catheter group [11% (7/66) compared with 6% (4/62), P < 0.05]. The double-balloon catheter group had significantly lower rates of contraction over frequency [0(0/66) compared with 42% (26/62), P < 0.05], hyperthermia [3% (2/66) compared with 19% (12/62), P < 0.05], fetal heart rate abnormalities before removing the device or drug [5% (3/66) compared with 19% (12/62), P < 0.05], as well as precipitate labour [2% (1/66) compared with 16% (10/62), P < 0.05].

CONCLUSIONS

The efficacy of a double- balloon transcervical catheter is similar to that of a prostaglandin vaginal insert. However, the double- balloon catheter cannot significantly reduce the cesarean section rate while it increases the risk of intrauterine infection. The maternal and fetal safety of transcervical catheter is superior to the prostaglandin vaginal insert. In cases of oligohydramnios, fetal growth restriction, pregnancy complicated with asthma, hypertension and scar uterine are in favor of a balloon catheter using for cervical ripening on account of high risk of using prostaglandin.

The impact of sweeping the membranes on cervical length and labor: a randomized clinical trial

OBJECTIVES

The aim of the study was to investigate to what extent sweeping of the membranes contributes to cervical shortening and if cervical shortening is related to the time to onset of labor and duration of the active phase of labor

METHODS

This prospective randomized clinical trial was performed at Baskent University between February and March 2011. Women were randomly assigned to receive membrane sweeping (Sweeping Group) (n = 69) or no membrane sweeping (Control Group) (n = 71). Cervical length was measured (cervix1) in both groups by examiner 1 and the Bishop Score was determined in the control group and sweeping was performed in the sweeping group by examiner 2. Two days later the patients had another cervical length measurement (cervix 2) by examiner 1, blinded to the group and results of the examiner 2. t test, Mann-Whitney U test and Chi-square test were used for statistical analyses.

RESULTS

Cervix 1 was 27.4 +/- 8.4 mm and 29.6 +/- 8.9 mm (p = 0.14), cervix 2 was 23.3 +/- 8.8 mm and 23.8 +/- 8.5 mm (p = 0.28) and cervical shortening was 5 +/- 4 mm and 5 +/-4 mm (p = 0.446), time to onset of labor was 6.3 +/- 4.6 and 5.7 +/- 4.7 (p = 0.38) and duration of labor was 5.8 +/- 2.89 and 5.7 +/- 2.4 (p = 0.82) for the sweeping and the control groups, respectively

CONCLUSIONS

Sweeping of the membranes does not reduce cervical length and does not shorten time to onset of labor and duration of the active phase of labor NCT 1309308: Sweeping the Membranes, Cervical Length and Duration of Labor

Labor induction in nulliparous women with an unfavorable cervix: double balloon catheter versus dinoprostone

OBJECTIVE

We sought to compare the efficacy of the double-balloon catheter and dinoprostone for induction of labor among nulliparous women with an unfavorable cervix.

STUDY DESIGN

Nulliparous women with a Bishop score <6 were randomized to receive a 10-mg intra-vaginal dinoprostone insert or a double-balloon catheter. Primary outcome was time to delivery. Statistical analyses were performed by intention to treat using the chi-square, Fisher's exact, and Student's t-test, as appropriate.

RESULTS

The mean induction-to-delivery time was shorter in the double-balloon group as compared to the dinoprostone group (17.9±5.8 vs. 26.3±9.7 h) as was the time from induction to vaginal delivery (19.13±5 vs. 24.45±8.7 h, respectively). More women in the catheter group were delivered within 24 h compared to the dinoprostone group (87.1% vs. 47.4%). Approximately 50% of women in both groups delivered by cesarean section.

CONCLUSION

Induction of labor with the double-balloon catheter in nulliparous women with an unfavorable cervix is associated with a shorter time to delivery compared to dinoprostone.

Significance of cervical ripening in pre-induction treatment for premature rupture of membranes at term

AIM

This study aimed to determine whether mechanical cervical dilatation with a laminaria tent in women with premature rupture of membranes (PROM) at term may influence the maternal/neonatal outcomes.

METHODS

We reviewed the medical records and histopathologic results of the placenta in 782 women with PROM at term. Of the 486 women seen prior to 2010 (group 1), 85 had Bishop scores of 5 or less and underwent insertion of laminaria tents (group A). In the 296 women admitted after 2010 (group 2), 27 had Bishop scores of 5 or less and underwent labor management without insertion of laminaria tents (group B). The patient characteristics, delivery course and neonatal outcomes were compared between the groups.

RESULTS

There were no significant differences in the maternal age, percentage of nulliparas, body mass index, gestational age at delivery or Bishop score between the groups. The Bishop score improved from 2.5 to 6.1 after laminaria tent insertion in group A. However, there were no significant intergroup differences in the frequency of use of labor-inducing agents or the time interval from PROM to delivery. The incidence of clinical/pathological chorioamnionitis was not higher in group A than in group B. No significant differences were found in the Apgar scores, umbilical artery pH or frequency of asphyxia neonatorum between the groups. Mechanical cervical dilatation by laminaria tent insertion neither increased the incidence of infection nor contributed to improvement of the perinatal prognosis.

CONCLUSION

Mechanical cervical dilatation does not provide any benefit for women with PROM at term.

Outpatient versus inpatient induction of labour for improving birth outcomes

BACKGROUND

More than 20% of women undergo induction of labour in some countries. The different methods used to induce labour have been the focus of previous reviews, but the setting in which induction takes place (hospital versus outpatient settings) may have implications for maternal satisfaction and costs. It is not known whether some methods of induction that are effective and safe in hospital are suitable in outpatient settings.

OBJECTIVES

To assess the effects on outcomes for mothers and babies of induction of labour for women managed as outpatients versus inpatients.

SEARCH METHODS

We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (30 June 2013).

SELECTION CRITERIA

Published and unpublished randomised and quasi-randomised trials in which inpatient and outpatient methods of cervical ripening or induction of labour have been compared.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed trial reports for inclusion. Two review authors carried out data extraction and assessment of risk of bias independently.

MAIN RESULTS

We included four trials, with a combined total of 1439 women in the review; each trial examined a different method of induction and we were unable to pool the results from trials.1. Vaginal PGE2 (two studies including 1028 women). There were no differences between women managed as outpatients versus inpatients for most review outcomes. There was no evidence of a difference between the likelihood of women requiring instrumental delivery in either setting (risk ratio (RR) 1.29; 95% confidence interval (CI) 0.79 to 2.13). The overall length of hospital stay was similar in the two groups.2. Controlled release PGE2 10 mg (one study including 300 women). There was no evidence of differences between groups for most review outcomes, including success of induction. During the induction period itself, women in the outpatient group were more likely to report high levels of satisfaction with their care (satisfaction rated seven or more on a nine-point scale, RR 1.42; 95% CI 1.11 to 1.81), but satisfaction scores measured postnatally were similar in the two groups.3. Foley catheter (one study including 111 women). There was no evidence of differences between groups for caesarean section rates, total induction time and the numbers of babies admitted to neonatal intensive care.

AUTHORS' CONCLUSIONS

The data available to evaluate the efficacy or potential hazards of outpatient induction are limited. It is, therefore, not yet possible to determine whether induction of labour is effective and safe in outpatient settings.

Inner thigh taping vs traction for cervical ripening with a Foley catheter: a randomized controlled trial

OBJECTIVE

To assess the effectiveness of inner thigh "Taping" compared with "Traction" using a weighted bag when an intracervical Foley catheter is used for cervical ripening.

STUDY DESIGN

We performed a randomized controlled trial at a tertiary hospital on women with a singleton pregnancy in cephalic presentation admitted for labor induction with a Bishop score ≤6. A 30 mL intracervical Foley catheter was placed for ripening. Women were randomly allocated to inner thigh Taping or to Traction with a 500 mL weighted bag of fluid. The primary outcome was time to delivery. Secondary outcomes were time to expulsion of the catheter, maternal discomfort (visual analog scale), mode of delivery, and maternal morbidities.

RESULTS

We randomized 197 women. After exclusions (4 ineligible, 2 withdrawn by provider), we analyzed 191 (96 Taping, 95 Traction) women in their assigned groups. Groups were similar regarding maternal race, age, parity, gestational age, and induction indication. Time to delivery was not significantly different (mean ± standard deviation: 19.8 ± 8.5 vs 18.8 ± 8.0 hours; P = .39). Time to catheter expulsion was shorter in the Traction Group (median, 2.6; range, 0.2-10.8 vs median, 1.5; range, 0.1-6.3 hours; P < .001). Change in Bishop and pain scores, cesarean delivery rates, clinical amnionitis, and other maternal morbidities were similar between groups. Subset analyses of those with vaginal delivery and among nulliparas, and multiparas revealed similar results.

CONCLUSION

Traction on the intracervical Foley catheter during cervical ripening shortens the time to spontaneous catheter expulsion without affecting the time to delivery.

Acupuncture for induction of labour

BACKGROUND

This is one of a series of reviews of methods of cervical ripening and labour induction using standardised methodology. The use of complementary therapies is increasing and some women look to complementary therapies during pregnancy and childbirth to be used alongside conventional medical practice. Acupuncture involves the insertion of very fine needles into specific points of the body. The limited observational studies to date suggest acupuncture for induction of labour appears safe, has no known adverse effects to the fetus, and may be effective. However, the evidence regarding the clinical effectiveness of this technique is limited.

OBJECTIVES

To determine the effectiveness and safety of acupuncture for third trimester cervical ripening or induction of labour.

SEARCH METHODS

We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (23 November 2012), PubMed (1966 to 23 November 2012), Embase (1980 to 23 November 2012), Dissertation Abstracts (1861 to 23 November 2012), CINAHL (1982 to 23 November 2012), the WHO International Clinical Trials Registry Portal (ICTRP) (23 November 2012) and bibliographies of relevant papers.

SELECTION CRITERIA

Clinical trials comparing acupuncture used for third trimester cervical ripening or labour induction with placebo/no treatment or other methods listed above it on a predefined list of labour induction methods.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed trials for inclusion, evaluated methodological quality and extracted data.

MAIN RESULTS

The original review included three trials and seven trials were excluded. This updated review includes 14 trials, and excludes eight trials. Three trials previously excluded due to no clinically relevant outcomes are now included. Eight new trials were included, and four new trials were excluded. We included 14 trials with data reporting on 2220 women.Trials reported on three primary outcomes only caesarean section, serious neonatal morbidity and maternal mortality. No trial reported on vaginal delivery not achieved within 24 hours; and uterine hyperstimulation with fetal heart rate (FHR) changes. There was no difference in caesarean deliveries between acupuncture and the sham control (average risk ratio (RR) 0.95, 95% confidence interval (CI) 0.69 to 1.30, six trials, 654 women), and acupuncture versus usual care (average RR 0.69, 95% CI 0.40, 1.20, six trials, 361 women). There was no difference in neonatal seizures between acupuncture and the sham group (RR 1.01, 95% CI 0.06 to 16.04, one trial, 364 women).There was some evidence of a change in cervical maturation for women receiving acupuncture compared with the sham control, (mean difference (MD) 0.40. 95%CI 0.11 to 0.69, one trial, 125 women), and when compared with usual care (MD 1.30, 95% CI 0.11 to 2.49, one trial, 67 women). The length of labour was shorter in the usual care group compared with acupuncture (average standardised mean difference (SMD) 0.67, 95% CI 0.18 to 1.17, one trial 68 women). There were no other statistically significant differences between groups. Few studies reported on many clinically relevant outcomes. One trial was at a low risk of bias on all domains.

AUTHORS' CONCLUSIONS

Overall, there have been few studies assessing the role of acupuncture for induction of labour. Before implications for clinical practice can be made there is a need for well-designed randomised controlled trials to evaluate the role of acupuncture to induce labour and for trials to assess clinically meaningful outcomes.

Castor oil, bath and/or enema for cervical priming and induction of labour

BACKGROUND

Castor oil, a potent cathartic, is derived from the bean of the castor plant. Anecdotal reports, which date back to ancient Egypt have suggested the use of castor oil to stimulate labour. Castor oil has been widely used as a traditional method of initiating labour in midwifery practice. Its role in the initiation of labour is poorly understood and data examining its efficacy within a clinical trial are limited. This is one of a series of reviews of methods of cervical ripening and labour induction using standardised methodology.

OBJECTIVES

To determine the effects of castor oil or enemas for third trimester cervical ripening or induction of labour in comparison with other methods of cervical ripening or induction of labour.

SEARCH METHODS

We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (30 April 2013) and bibliographies of relevant papers.

SELECTION CRITERIA

Clinical trials comparing castor oil, bath or enemas used for third trimester cervical ripening or labour induction with placebo/no treatment or other methods listed above it on a predefined list of labour induction methods.

DATA COLLECTION AND ANALYSIS

A strategy was developed to deal with the large volume and complexity of trial data relating to labour induction. This involved a two-stage method of data extraction.

MAIN RESULTS

Three trials, involving 233 women, are included. There was no evidence of differences in caesarean section rates between the two interventions in the two trials reporting this outcome (risk ratio (RR) 2.04, 95% confidence interval (CI) 0.92 to 4.55). There were no data presented on neonatal or maternal mortality or morbidity.There was no evidence of a difference between castor oil and placebo/no treatment for the rate of instrumental delivery, meconium-stained liquor, or Apgar score less than seven at five minutes. The number of participants was too small to detect all but large differences in outcome. All women who ingested castor oil felt nauseous (RR 59.92, 95% CI 8.46 to 424.52).

AUTHORS' CONCLUSIONS

The three trials included in the review contain small numbers of women. All three studies used single doses of castor oil. The results from these studies should be interpreted with caution due to the risk of bias introduced due to poor methodological quality. Further research is needed to attempt to quantify the efficacy of castor oil as an cervical priming and induction agent.

Imaging analysis of cervical elastography for prediction of successful induction of labor at term

OBJECTIVES

The aim of this study was to evaluate the value of imaging analysis of cervical elastography to predict successful induction of labor in nulliparous women at term.

METHODS

Successful labor induction was defined as onset of active labor within 9 hours or delivery within 24 hours. The Bishop score, cervical length, and cervical elastographic parameters, including cervical area, mean elastographic index, and cervical hard area, were measured and analyzed by the image analyzer.

RESULTS

The areas under the curves for the cervical length, cervical area, Bishop score, mean elastographic index, and cervical hard area were 0.63, 0.64, 0.47, 0.68, and 0.70, respectively, for onset of active labor within 9 hours and 0.70, 0.68, 0.63, 0.71, and 0.76 for delivery within 24 hours. The combination of cervical length and elastographic data was more predictable for successful labor induction (P < .05).

CONCLUSIONS

Imaging analysis of cervical elastography is available to predict successful induction of labor.

[Efficacy of double-balloon catheter for cervical ripening and labor induction]

OBJECTIVE

To study the indication, efficacy, and safety of double-balloon catheter for cervical ripening and labor induction in term pregnant women.

METHODS

A total of 586 pregnant women using double-balloon catheters from May 2011 to October 2012 were divided into three groups according to their initial Bishop scores: group 1 (Bishop score < or = 3, n = 155), group 2 (Bishop score 4-5, n = 223) and group 3 (Bishop score > or = 6, n = 208). The control group (Bishop score > or = 6, n = 112) were directly given low-dose of oxytocin through continuous intravenous infusion for labor induction.

RESULTS

(1) The effective rate of cervical ripening and the success rate of vaginal delivery in group 1, 2 and 3 were gradually increased, with significantly differences among the three groups. The rate and the duration of oxytocin infusion were gradually decreased in group 1, 2 and 3, also with significantly differences. (2) The success rate of vaginal delivery in group 3 was significantly higher than that in control group. The average total labor stage of group 3 was significantly shorter than that of control group. The complications of mothers and fetus showed no significant difference between the two groups.

CONCLUSION

The efficacy of double-balloon catheter for cervical ripening and labor induction was closely associated with the Bishop score. It is suitable in pregnant women with higher Bishop score.

A randomized trial of preinduction cervical ripening: dinoprostone vaginal insert versus double-balloon catheter

OBJECTIVE

We sought to compare the efficacy of a double-balloon transcervical catheter to that of a prostaglandin (PG) vaginal insert among women undergoing labor induction.

STUDY DESIGN

In all, 210 women with a Bishop score ≤6 were assigned randomly to cervical ripening with either a double-balloon device or a PGE2 sustained-release vaginal insert. Primary outcome was vaginal delivery within 24 hours.

RESULTS

The proportion of women who achieved vaginal delivery in 24 hours was higher in the double-balloon group than in the PGE2 group (68.6% vs 49.5%; odds ratio, 2.22; 95% confidence interval, 1.26-3.91). There was no difference in cesarean delivery rates (23.8% vs 26.2%; odds ratio, 0.88; 95% confidence interval, 0.47-1.65). Oxytocin and epidural analgesia were administered more frequently when a double-balloon device was used. Uterine tachysystole or hypertonus occurred more frequently in the PGE2 arm (9.7% vs 0%, P = .0007).

CONCLUSION

The use of a double-balloon catheter for cervical ripening is associated with a higher rate of vaginal birth within 24 hours compared with a PGE2 vaginal insert.

Induction of labor in a contemporary obstetric cohort

OBJECTIVE

We sought to describe details of labor induction, including precursors and methods, and associated vaginal delivery rates.

STUDY DESIGN

This was a retrospective cohort study of 208,695 electronic medical records from 19 hospitals across the United States, 2002 through 2008.

RESULTS

Induction occurred in 42.9% of nulliparas and 31.8% of multiparas and elective or no recorded indication for induction at term occurred in 35.5% and 44.1%, respectively. Elective induction at term in multiparas was highly successful (vaginal delivery 97%) compared to nulliparas (76.2%). For all precursors, cesarean delivery was more common in nulliparas in the latent compared to active phase of labor. Regardless of method, vaginal delivery rates were higher with a ripe vs unripe cervix, particularly for multiparas (86.6-100%).

CONCLUSION

Induction of labor was a common obstetric intervention. Selecting appropriate candidates and waiting longer for labor to progress into the active phase would make an impact on decreasing the national cesarean delivery rate.

Quantification of cervical elastography: a reproducibility study

OBJECTIVES

To assess a new method for numerical quantification of cervical elastography during pregnancy and to evaluate the repeatability of the measurements.

METHODS

Cervical elastography was carried out twice by a single operator in 112 singleton pregnancies at a median of 21 (range, 12-40) weeks' gestation. In 50 of the cases a second operator performed another elastography measurement. The intraobserver and interobserver repeatability of measurements in different parts of the cervix were assessed using intraclass correlation coefficients with 95% CI and by Bland-Altman analysis.

RESULTS

There were no statistically significant differences in the elastography measurements made by the same and by two different observers in each area measured, except in the area that receives the force of the transducer directly. The distribution of elastographic measurements obtained in different regions of the cervix demonstrated that the external and superior parts were significantly softer than the internal and inferior parts.

CONCLUSION

It is possible to provide an objective quantification of elastographic colors in the cervix. The measurements obtained by elastography may be a mere reflection of the force being applied by the transducer to different parts of the cervix. It is too premature to suggest that the measurements of rate-of-change in tissue displacement reflect histological changes that could provide a measure of cervical ripening.

Mechanical methods for induction of labour

BACKGROUND

Mechanical methods were the first methods developed to ripen the cervix and induce labour. During recent decades they have been substituted by pharmacological methods. Potential advantages of mechanical methods, compared with pharmacological methods, may include simplicity of preservation, lower cost and reduction of the side effects.

OBJECTIVES

To determine the effects of mechanical methods for third trimester cervical ripening or induction of labour in comparison with placebo/no treatment, prostaglandins (vaginal and intracervical prostaglandin E2 (PGE2), misoprostol) and oxytocin.

SEARCH METHODS

We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (30 April 2011) and bibliographies of relevant papers. We updated this search on 16 January 2012 and added the results to the awaiting classification section of the review.

SELECTION CRITERIA

Clinical trials comparing mechanical methods used for third trimester cervical ripening or labour induction with methods listed above it on a predefined list of methods of labour. A comparison with amniotomy will be added, should this comparison be made in future trials.Different types of intervention have been considered as mechanical methods: (1) introduction of laminaria tents, or their synthetic equivalent (Dilapan), into the cervical canal; (2) the introduction of a catheter through the cervix into the extra-amniotic space, with or without traction; (3) use of a catheter to inject fluidsin the extra-amniotic spaceIn addition, we made other comparisons: (1) specific mechanical methods (balloon catheter and laminaria tents) compared with any prostaglandins or with oxytocin; (2) addition of prostaglandins or oxytocin to mechanical methods compared with prostaglandins alone.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed trials for inclusion and assessed risk of bias. Two review authors independently extracted data.

MAIN RESULTS

For this update we have included a further 27 studies. The review includes 71 randomised controlled trials (total of 9722 women), ranging from 39 to 588 women per study. Most studies reported on caesarean section, all other outcomes are based on substantially fewer women. Four additional studies are ongoing.Mechanical methods versus no treatment: one study (48 woman) reported on women who did not achieve vaginal delivery within 24 hours (risk ratio (RR) 0.90; 95% confidence interval (CI) 0.64 to 1.26). The risk of caesarean section was similar between groups (six studies; 416 women, RR 1.00; 95% CI 0.76 to 1.30). There were no cases of severe neonatal and maternal morbidity.Mechanical methods versus vaginal PGE2 (17 studies;1894 woman): The proportion of women who did not achieve vaginal delivery within 24 hours was not significantly different (three studies; 586 women RR 1.72; 95% CI 0.90 to 3.27); however, for the subgroup of multiparous women the risk of not achieving delivery within 24 hours was higher (one study; 147 women RR 4.38, 95% CI 1.74 to 10.98), with no increase in caesarean sections (RR 1.19, 95% CI 0.62-2.29). Compared with intracervical PGE2 (14 studies;1784 women and misoprostol there was no significant difference in the proportion of women not achieving vaginal delivery within 24 hours.Mechanical methods reduced the risk of hyperstimulation with fetal heart rate changes when compared with vaginal prostaglandins: vaginal PGE2 (eight studies; 1203 women, RR 0.16; 95% CI 0.06 to 0.39) and misoprostol (3% versus 9%) (nine studies; 1615 women, RR 0.37; 95% CI 0.25 to 0.54). Risk of caesarean section between mechanical methods and prostaglandins was comparable. Serious neonatal and maternal morbidity were infrequently reported and did not differ between the groups.Mechanical methods compared with induction with oxytocin (reduced the risk of caesarean section (five studies; 398 women, RR 0.62; 95% CI 0.42 to 0.90). The likelihood of vaginal delivery within 24 hours was not reported. Hyperstimulation with fetal heart rate changes was reported in one study (200 participants), and did not differ. There were no reported cases of severe maternal or neonatal morbidity.

AUTHORS' CONCLUSIONS

Induction of labour using mechanical methods results in similar caesarean section rates as prostaglandins, for a lower risk of hyperstimulation. Mechanical methods do not increase the overall number of women not delivered within 24 hours, however the proportion of multiparous women who did not achieve vaginal delivery within 24 hours was higher when compared with vaginal PGE2. Compared with oxytocin, mechanical methods reduce the risk of caesarean section.

The efficacy of dinoprostone vaginal insert for active management of premature rupture of membranes at term: a randomized controlled trial

PURPOSE

To evaluate the efficacy and safety of the vaginal insertion of dinoprostone in terms of achieving cervical ripening, shortening the length of labor, and lowering the cesarean delivery rate for term pregnancies complicated with premature rupture of membranes.

METHODS

A prospective, randomized, controlled trial enrolled 100 women with term pregnancies complicated with premature rupture of membranes. Each had a normal non stress test, unscarred uterus, a singleton pregnancy with cephalic presentation, and a Bishop score of less than 4. Patients were randomized to receive a 10 mg dinoprostone vaginal insert single dose or no medication. After cervical ripening, oxytocin induction was performed during labor for both the study and control group. Cervical ripening in the 12th hour, total delivery time and delivery mode were compared between the two groups.

RESULTS

More often cervical ripening was obtained in the study group women who used dinoprostone vaginal inserts compared to the control group (p: 0.001). Latent phase of labor and total delivery time was shorter in the study group women than the control group (p: 0.022 and p: 0.026). There was no difference in terms of delivery mode and indication of section between study and control groups.

CONCLUSION

The use of dinoprostone vaginal inserts in patients with term pregnancy of premature rupture of membranes reduced both the latent phase of labor and total delivery time without increasing the rate of cesarean section.

Foley catheter versus vaginal prostaglandin E2 gel for induction of labour at term (PROBAAT trial): an open-label, randomised controlled trial

BACKGROUND

Induction of labour is a common obstetric procedure. Both mechanical (eg, Foley catheters) and pharmacological methods (eg, prostaglandins) are used for induction of labour in women with an unfavourable cervix. We aimed to compare the effectiveness and safety of induction of labour with a Foley catheter with induction with vaginal prostaglandin E2 gel.

METHODS

We did an open-label, randomised controlled trial in 12 hospitals in the Netherlands between Feb 10, 2009, and May 17, 2010. We enrolled women with a term singleton pregnancy in cephalic presentation, intact membranes, an unfavourable cervix, an indication for induction of labour, and no prior caesarean section. Participants were randomly allocated by an online randomisation system to induction of labour with a 30 mL Foley catheter or vaginal prostaglandin E2 gel (1:1 ratio). Because of the nature of the intervention this study was not blinded. The primary outcome was caesarean section rate. Secondary outcomes were maternal and neonatal morbidity and time from intervention to birth. All analyses were done on an intention-to-treat basis. We also did a meta-analysis that included our trial. The trial was registered with the Dutch trial registry, number NTR 1646.

FINDINGS

824 women were allocated to induction of labour with a Foley catheter (n=412) or vaginal prostaglandin E2 gel (n=412). Caesarean section rates were much the same between the two groups (23%vs 20%, risk ratio [RR] 1·13, 95% CI 0·87-1·47). A meta-analysis including our trial data confirmed that a Foley catheter did not reduce caesarean section rates. We recorded two serious maternal adverse events, both in the prostaglandin group: one uterine perforation and one uterine rupture.

INTERPRETATION

In women with an unfavourable cervix at term, induction of labour with a Foley catheter is similar to induction of labour with prostaglandin E2 gel, with fewer maternal and neonatal side-effects.

FUNDING

None.

Is transcervical Foley catheter actually slower than prostaglandins in ripening the cervix? A randomized study

OBJECTIVE

The purpose of this study was to determine whether the maximum time for cervical ripening (from 24-12 hours) would influence the efficacy of a transcervical Foley catheter and to compare efficacy to that of a prostaglandin E(2) vaginal insert.

STUDY DESIGN

Three hundred ninety-seven women were assigned randomly to (1) Foley catheter left in place for a maximum of 24 hours, (2) Foley catheter left in place for a maximum of 12 hours, or (3) prostaglandin E(2) controlled-release vaginal insert. Primary outcome was vaginal delivery within 24 hours.

RESULTS

There were no differences in vaginal delivery rates. The proportion of women who achieved vaginal delivery in 24 hours was lower in the 24-hour Foley catheter group than in the other 2 groups (24-hour Foley catheter, 21.0%; 12-hour Foley catheter, 59.8%; vaginal prostaglandin E(2), 48.5%; P < .0001).

CONCLUSION

Cutting the ripening time with a Foley catheter by one-half increases the proportion of women who deliver vaginally within 24 hours and yields efficacy similar to that of prostaglandin E(2) vaginal insert.

Effect of membrane sweeping on cervical length by transvaginal ultrasonography and impact of cervical shortening on cesarean delivery

OBJECTIVES

The purpose of this study was to evaluate cervical length changes after membrane sweeping and the effect of cervical shortening on pregnancy outcomes.

METHODS

Low-risk women at 40 weeks' gestation undergoing membrane sweeping to expedite labor were recruited. Participants were scheduled for labor induction at 41 weeks' gestation. Transvaginal ultrasonography was performed immediately before and after membrane sweeping to measure the cervical length. Three presweep and postsweep cervical lengths were measured. The shortest lengths before and after the sweep were taken as the representative lengths. The effect of membrane sweeping on cervical length was analyzed. Multivariable logistic regression analysis was performed to evaluate the effect of cervical shortening on labor induction and the mode of delivery.

RESULTS

For the 160 participants, the mean presweep cervical length ± SD was 21.0 ± 10.0 mm; the postsweep length was 23.8 ± 10.9 mm, an average increase of 2.8 ± 0.6 mm (P < .001). Cervical shortening after membrane sweeping was noted in 53 of 160 cases (33%). Cervical shortening was associated with a reduction in all-cause cesarean delivery but not labor induction on bivariate analysis. After adjustment for maternal age, parity, presweep Bishop score, postsweep cervical length, oxytocin augmentation, epidural analgesia, and meconium-stained fluid, cervical shortening after membrane sweeping was independently predictive of a reduction in cesarean deliveries (adjusted odds ratio, 0.24; 95% confidence interval, 0.06-0.90; P = .034).

CONCLUSIONS

Membrane sweeping was associated with lengthening of the cervix. A shortened cervix after sweeping was independently predictive of vaginal delivery.

Vaginal misoprostol for cervical ripening and induction of labour

BACKGROUND

Misoprostol (Cytotec, Searle) is a prostaglandin E1 analogue widely used for off-label indications such as induction of abortion and of labour. This is one of a series of reviews of methods of cervical ripening and labour induction using standardised methodology.

OBJECTIVES

To determine the effects of vaginal misoprostol for third trimester cervical ripening or induction of labour.

SEARCH STRATEGY

The Cochrane Pregnancy and Childbirth Group's Trials Register (November 2008) and bibliographies of relevant papers. We updated this search on 30 April 2010 and added the results to the awaiting classification section.

SELECTION CRITERIA

Clinical trials comparing vaginal misoprostol used for third trimester cervical ripening or labour induction with placebo/no treatment or other methods listed above it on a predefined list of labour induction methods.

DATA COLLECTION AND ANALYSIS

We developed a strategy to deal with the large volume and complexity of trial data relating to labour induction. This involved a two-stage method of data extraction.We used fixed-effect Mantel-Haenszel meta-analysis for combining dichotomous data.If we identified substantial heterogeneity (I² greater than 50%), we used a random-effects method.

MAIN RESULTS

We included 121 trials. The risk of bias must be kept in mind as only 13 trials were double blind.Compared to placebo, misoprostol was associated with reduced failure to achieve vaginal delivery within 24 hours (average relative risk (RR) 0.51, 95% confidence interval (CI) 0.37 to 0.71). Uterine hyperstimulation, without fetal heart rate (FHR) changes, was increased (RR 3.52 95% CI 1.78 to 6.99).Compared with vaginal prostaglandin E2, intracervical prostaglandin E2 and oxytocin, vaginal misoprostol was associated with less epidural analgesia use, fewer failures to achieve vaginal delivery within 24 hours and more uterine hyperstimulation. Compared with vaginal or intracervical prostaglandin E2, oxytocin augmentation was less common with misoprostol and meconium-stained liquor more common.Lower doses of misoprostol compared to higher doses were associated with more need for oxytocin augmentation and less uterine hyperstimulation, with and without FHR changes.We found no information on women's views.

AUTHORS' CONCLUSIONS

Vaginal misoprostol in doses above 25 mcg four-hourly was more effective than conventional methods of labour induction, but with more uterine hyperstimulation. Lower doses were similar to conventional methods in effectiveness and risks. The authors request information on cases of uterine rupture known to readers. The vaginal route should not be researched further as another Cochrane review has shown that the oral route of administration is preferable to the vaginal route. Professional and governmental bodies should agree guidelines for the use of misoprostol, based on the best available evidence and local circumstances.

Evaluation of patients' satisfaction of cervical ripening using dinoprostone by either intravaginal gel or pessary: an open-label, randomized, prospective study

OBJECTIVE

To evaluate patient satisfaction of cervical ripening using dinoprostone (PGE2) by either intravaginal gel or pessary.

STUDY DESIGN

A group of 173 nulliparous women requiring cervical ripening were recruited in the study and randomized to receive either intravaginal gel (Prepidil, Upjohn, Milan, Italy [group A]) or intravaginal pessary (Propess, Ferring Pharmaceuticals, Malmö, Sweden [group B]). Before administration of PGE2 and after delivery, the patients answered a questionnaire investigating the anxiety and discomfort caused by cervical ripening.

RESULTS

Of the group, 22 women did not adequately complete the questionnaire; therefore 151 women were included in the study. Before cervical ripening, anxiety and discomfort did not significantly differ between the two study groups; more patients in group A than in group B declared they would have preferred the other form of application. The intensity of pain experienced during the application of PGE2 was higher in group B than in group A. For the future opportunity to choose the application necessary for cervical ripening, more patients in group B than in group A would change the form of application.

CONCLUSION

Patient satisfaction with the two forms of treatment appears to be equally good. The application of the intravaginal pessary causes more discomfort than the vaginal gel.

Ultrasonic attenuation estimation of the pregnant cervix: a preliminary report

OBJECTIVE

Estimates of ultrasonic attenuation (the loss of energy as an ultrasonic wave propagates through tissue) have been used to evaluate the structure and function of tissues in health and disease. The purpose of this research was to develop a method to estimate ultrasonic cervical attenuation during human pregnancy using a clinical ultrasound system.

METHODS

Forty women underwent a cervical scan once during pregnancy with the Zonare z.one clinical ultrasound system using a 4-9-MHz endovaginal transducer. This ultrasound system provides access to radiofrequency (RF) image data for processing and analysis. In addition, a scan of a tissue-mimicking phantom with a known attenuation coefficient was acquired and used as a reference. The same settings and transducer used in the clinical scan were used in the reference scan. Digital data of the beam-formed image were saved in Digital Imaging and Communications in Medicine (DICOM) format on a flash drive and converted to RF data on a personal computer using a Matlab program supplied by Zonare. Attenuation estimates were obtained using an algorithm that was independently validated using tissue-mimicking ultrasonic phantoms.

RESULTS

RF data were acquired and analyzed to estimate attenuation of the human pregnant cervix. Regression analysis revealed that attenuation was: a predictor of the interval from ultrasound examination to delivery (beta = 0.43, P = 0.01); not a predictor of gestational age at time of examination (beta = - 0.23, P = 0.15); and not a predictor of cervical length (beta = 0.077, P = 0.65).

CONCLUSIONS

Ultrasonic attenuation estimates have the potential to be an early and objective non-invasive method to detect interval between examination and delivery. We hypothesize that a larger sample size and a longitudinal study design will be needed to detect gestational age-associated changes in cervical attenuation.

Electroacupuncture for cervical ripening prior to labor induction: a randomized clinical trial

PURPOSE

The present study was aimed to compare the effects of the use of electroacupuncture and misoprostol in inducing labor in patients with Bishop score < 7 and to observe the characteristics of labor in both methods.

METHODS

As much as 67 pregnant women with Bishop score < 7, single cephalic presentation with gestational age confirmed by first-trimester ultrasound, reactive cardiotocography, and amniotic fluid volume and estimated fetal weight within the respective normal ranges for gestational age were selected. They were randomized into 2 groups: electroacupuncture (AC) or misoprostol (M).

RESULTS

There were no significant differences regarding age, gestational age, fetal weight, parity, Bishop score, or indication for induction. Labor was the main outcome, which was obtained in both groups without significant difference regarding frequency (p = 0.07) and time of induction (p = 0.29). Absence of obstetric complication, higher duration of labor (p = 0.036), and tendency to a higher satisfaction of the patients (p = 0.046) were observed among patients of group AC. Higher frequency of cesarean sections (p = 0.014) and obstetric complications (9.3%) were observed among patients of group M.

CONCLUSIONS

Our results showed that electroacupuncture can be used to obtain cervical ripening, with similar results as compared with misoprostol, with a significantly higher frequency of vaginal deliveries and without occurrence of obstetric complications.

[Comparison of the predictive value of digital examination (Bishop's score) and ultrasound evaluation for labor induction success]

AIM

Cervical ripening is the main factor of success in the induction of labor. The aim of the study was to compare predictive value of digital examination (Bishops score) and ultrasound evaluation for labor induction success.

MATERIAL AND METHODS

The study was carried out in the Fetal Medicine Department of Medical University of Lodz between 2006-2009. 101 pregnant women comprised the study group.

RESULTS

Comparing the subgroups with successful and unsuccessful labor induction, the main differences were observed in the entire Bishop's score (7.21 versus 5.4 points; p < 0.001). Ultrasound measurements demonstrated significant differences in the cervical diameter (55.5 vs. 51.6 mm; p < 0.01) and internal os (8.64 vs. 3.28 mm; p < 0.001). We noticed a significant correlation between the outcome of the labor induction and the shape of the canal (p < 0.001), as well as the posterior cervical angle (p < 0.001). Ultrasound measurements of the internal os width (p < 0.001; cut-off point: 4.5 mm), the length (p < 0.001; cut-off point: 23.5 mm) and shape of the cervical canal (p < 0.001; Y shape in 36.21%), were significant independent factors in the prediction of labor induction. Following the Bishop's score model, we created a similar score for the ultrasound measurements (total -10 points). The entire score of the ultrasound measurements with the cut-off value: 4.5 points, was found to be a significant factor (p < 0.001) predicting the success of labor induction.

CONCLUSION

The ultrasound evaluation of the cervix demonstrates significantly better predictive value in the prognosis of labor induction comparing to the Bishop's score.

[Effectiveness of intracervical catheter as a labor preinduction method]

OBJECTIVES

This study was undertaken to determine the efficacy and safety of the Foley catheter as a cervical priming agent.

MATERIAL AND METHODS

Data analysis concern 327 women undergoing cervical ripening with intracervical Foley catheter. The primary measured outcome was ripening of the cervix as measured with the Bishop score. The secondary outcomes were the timings starting from balloon removal (or from spontaneous expulsion) to delivery the preinduction-delivery interval, mode of delivery frequency of side effects and neonatal outcome.

RESULTS

The most common indications for induction were post-term and non-reassuring fetal status. Intracervical Foley catheter was retained for mean duration of 15 hours 35 minutes. Bishop score rise after preinduction time was statistically significant (3.29 +/- 1.16 at the balloon insertion; 6.85 +/- 1.7 at the removal of the Foley catheter). Mean Bishop score change was 3.56 +/- 1.58. The average interval from balloon expulsion to delivery was 8 hours 27 minutes, the preinduction-delivery interval - 24 hours 3 minutes. Out of 327 women undergoing cervical ripening with the Foley catheter 236 (72.17%) had vaginal delivery 91 (27.38%)--cesarean delivery. The rate of vaginal delivery was significantly higher in the multiparous group (85.32%) when compared to nulliparous (65.6%). In 312 neonates (94.8%), the Apgar score at 3 min was more than 8.

CONCLUSIONS

Intracervical Foley catheter is an effective and safe agent for cervical ripening.

Abnormal 1 hour glucose challenge test followed by a normal 3 hour glucose tolerance test: does it identify adverse pregnancy outcome?

OBJECTIVE

To determine if pregnancies with an abnormal glucose challenge test (GCT) but a normal (GTT) are at increased risk for fetal macrosomia or an adverse pregnancy outcome.

STUDY DESIGN

This prospective observational study matched women with an abnormal glucose challenge test and a normal GTT with the next patient with a normal GCT.

RESULTS

Over 12 months, 107 women with abnormal GCT were matched with 107 women with normal GCT. Women with an abnormal GCT were older (27.3 vs. 24.7, p = 0.001) and less likely to be African-American (OR = 2.2, 95% CI 1.06-4.49) but no more likely to have an adverse pregnancy outcome. ROC curves could not differentiate between macrosomic vs non-macrosomic newborns using GCT values.

CONCLUSION

Women with an abnormal GCT but a normal GTT are more likely to be older, less likely to be African-American, but no more likely to have an adverse pregnancy outcome or a macrosomic fetus.

Intravenous oxytocin alone for cervical ripening and induction of labour

BACKGROUND

Oxytocin is the commonest induction agent used worldwide. It has been used alone, in combination with amniotomy or following cervical ripening with other pharmacological or non-pharmacological methods.

OBJECTIVES

To determine the effects of oxytocin alone for third trimester cervical ripening and induction of labour in comparison with other methods of induction of labour or placebo/no treatment.

SEARCH STRATEGY

We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (January 2009) and bibliographies of relevant papers.

SELECTION CRITERIA

Randomised and quasi-randomised trials comparing intravenous oxytocin with placebo or no treatment, or with prostaglandins (vaginal or intracervical) for third trimester cervical ripening or labour induction.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed eligibility and carried out data extraction.

MAIN RESULTS

Sixty-one trials (12,819 women) are included.When oxytocin inductions were compared with expectant management, fewer women failed to deliver vaginally within 24 hours (8.4% versus 53.8%, risk ratio (RR) 0.16, 95% confidence interval (CI) 0.10 to 0.25). There was a significant increase in the number of women requiring epidural analgesia (RR 1.10, 95% CI 1.04 to 1.17). Fewer women were dissatisfied with oxytocin induction in the one trial reporting this outcome (5.9% versus 13.7%, RR 0.43, 95% CI 0.33 to 0.56).Compared with vaginal prostaglandins, oxytocin increased unsuccessful vaginal delivery within 24 hours in the two trials reporting this outcome (70% versus 21%, RR 3.33, 95% CI 1.61 to 6.89). There was a small increase in epidurals when oxytocin alone was used (RR 1.09, 95% CI 1.01 to 1.17).Most of the studies included women with ruptured membranes, and there was some evidence that vaginal prostaglandin increased infection in mothers (chorioamnionitis RR 0.66, 95% CI 0.47 to 0.92) and babies (use of antibiotics RR 0.68, 95% CI 0.53 to 0.87). These data should be interpreted cautiously as infection was not pre-specified in the original review protocol.When oxytocin was compared with intracervical prostaglandins, there was an increase in unsuccessful vaginal delivery within 24 hours (50.4% versus 34.6%, RR 1.47, 95% CI 1.10 to 1.96) and an increase in caesarean sections (19.1% versus 13.7%, RR 1.37, 95% CI 1.08 to 1.74) in the oxytocin group.

AUTHORS' CONCLUSIONS

Comparison of oxytocin with either intravaginal or intracervical PGE2 reveals that the prostaglandin agents probably increase the chances of achieving vaginal birth within 24 hours. Oxytocin induction may increase the rate of interventions in labour.A suggestion that for women with prelabour rupture of membranes induction with vaginal prostaglandin may increase risk of infection for mother and baby warrants further study.

[Premature rupture membrane at term with unfavourable cervix]

BACKGROUND

Between expectant attitude in hospital and labour induction, management of and premature rupture membrane at term stay controversial.

AIM

The aim of our study was to evaluate the management rupture of the membranes at term with unfavourable cervix.

MATERIAL AND METHODS

We conducted a retrospective study. An expectant delay of 24 hours had been followed by induction labour in women with favourable Bishop. Maturation by prostaglandins E2 (PGE2) was performed in case of unfavourable cervix. We administrate one dose each 24 hours (3 doses maxima). Over, labour induction by ocytocine was started. The prescription of antibioprophylaxis is systematic until delivery.

RESULTS

We included 137 patients. 51% of patients had a spontaneous labour during the expectant delay. There was no significant difference in neonatal and maternal morbidity in case of expectant management of premature rupture membrane at term.

CONCLUSION

Based on our findings and a review of the literature, an expectative of 24 hours is interesting in case if unfavourable conditions. Prostaglandin E2 maturations can be performed in unfavourable cervixes.

A randomized controlled trial of acupuncture for initiation of labor in nulliparous women

OBJECTIVE

To evaluate the utility of outpatient acupuncture for labor stimulation.

METHODS

Nulliparous women at 39 4/7 weeks or greater with a singleton gestation and Bishop score of less than 7 were randomized to usual medical care (control group) versus usual care and three outpatient acupuncture treatments (acupuncture group). Each treatment consisted of eight needles applied to bilateral points LI4, SP6, UB31, and UB32. The primary outcome was time elapsed from the time of randomization to delivery. Secondary outcomes included rates of cesarean section and induction of labor. Medical records were abstracted for maternal demographic, medical, and delivery outcome data. A priori sample size calculation revealed that 56 women were required to detect a 72-hour difference in delivery time with a power of 83% and an alpha of 0.05. Student's t-test, Chi-square, and Kaplan-Meier statistics were used to compare groups.

RESULTS

Fifty-six women were randomized and completed the study procedures. Race, age, gestational age, and cervical Bishop score were similar in both groups. Mean time to delivery occurred 21 hours sooner in the acupuncture group, but this difference did not reach statistical significance (p = 0.36). Compared to controls, women in the acupuncture group tended to be more likely to labor spontaneously (70% vs. 50%, p = 0.12) and less likely to deliver by cesarean section (39% vs. 17%, p = 0.07). Of women who were not induced, those in the acupuncture group were more likely to be delivered than the controls at any point after enrollment (p = 0.05).

CONCLUSION

Acupuncture is well tolerated among term nulliparous women and holds promise in reducing interventions that occur in post-term pregnancies.

Consequences of routine delivery at 38 weeks for A-2 gestational diabetes

OBJECTIVE

To report our intrapartum experience with routine delivery at 38 weeks of gestation of A-2 diabetic pregnancies requiring primarily oral hypoglycemic therapy.

METHODS

This retrospective study consisted of 143 consecutive women with gestational diabetes not controlled with diet alone (A-2). Each underwent a routine trial of labor at 38 weeks of gestation. The preinduction condition of the cervix, need for oxytocin, and primary cesarean rates were primary endpoints. For comparison, a control group during that same period consisted of 137 consecutive diet-controlled diabetic (A-1) pregnancies with the same eligibility criteria who underwent expectant management at 38 weeks.

RESULTS

The study group was more likely to have an unfavorable cervix (75% versus 45%; p < 0.001) and to require oxytocin (76% versus 56%; p < 0.001). Early onset meconium was less common in the study group (3.5% versus 13.1%; p < 0.01). Primary cesarean rates were low and not different between the study and control groups (12.7% versus 11.7%; p < 0.8). The only stillbirth was in the control group and was associated with a tight double nuchal cord encirclement. Mean birth weights and the frequency of birth weights > 4000 g were not different between groups. Shoulder dystocia, low Apgar scores, and admissions to the special care nursery were infrequent in either group. No respiratory difficulties requiring resuscitation or prolonged nursery care were encountered.

CONCLUSION

Routine delivery at 38 weeks in an A-2 diabetic population is not associated with additional intrapartum morbidity or a greater need for cesarean delivery.

Outpatient versus inpatient induction of labour for improving birth outcomes

BACKGROUND

More than 20% of women undergo induction of labour in some countries. The different methods used to induce labour have been the focus of previous reviews, but the setting in which induction takes place (hospital versus outpatient settings) may have implications for maternal satisfaction and costs. It is not known whether some methods of induction that are effective and safe in hospital are suitable in outpatient settings.

OBJECTIVES

To assess the effects on outcomes for mothers and babies of induction of labour for women managed as outpatients versus inpatients.

SEARCH STRATEGY

We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (December 2008).

SELECTION CRITERIA

Published and unpublished randomised and quasi-randomised trials in which inpatient and outpatient methods of cervical ripening or induction of labour have been compared.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed trial reports for inclusion. Two review authors carried out data extraction and assessment of risk of bias independently.

MAIN RESULTS

We included three trials, with a combined total of 612 women in the review; each examined a different method of induction and we were unable to pool the results from trials.1. Vaginal PGE2 (One study including 201 women). There were no differences between women managed as out- versus inpatients for most review outcomes. Women in the outpatient group were more likely to have instrumental deliveries (risk ratio (RR) 1.74; 95% confidence interval (CI) 1.03 to 2.93). The overall length of hospital stay was similar in the two groups.2. Controlled release PGE2 10mg (one study including 300 women). There was no evidence of differences between groups for most review outcomes, including success of induction. During the induction period itself, women in the outpatient group were more likely to report high levels of satisfaction with their care (satisfaction rated seven or more on a nine-point scale RR 1.42; 95% CI 1.11 to 1.81), but satisfaction scores measured postnatally were similar in the two groups.3. Foley catheter (one study including 111 women). There was no evidence of differences between groups for caesarean section rates, total induction time and the numbers of babies admitted to neonatal intensive care.

AUTHORS' CONCLUSIONS

The data available to evaluate the efficacy or potential hazards of outpatient induction are limited. It is, therefore, not yet possible to determine whether induction of labour is effective and safe in outpatient settings.

Cervix remodeling and parturition in the rat: lack of a role for hypogastric innervation

The hypogastric nerve is a major pathway innervating the uterine cervix, yet its contribution to the processes of cervical ripening and parturition is not known. The main objective of this study was to determine the effect of hypogastric nerve transection on remodeling of the cervix and timing of birth. As an initial goal, processes associated with remodeling of the peripartum cervix were studied. The cervix was obtained from time-dated pregnant rats on days 15, 19, 21, and 21.5 of pregnancy, and post partum on the day of birth (day 22). The cervix was excised, post-fixed overnight, and sections stained to evaluate collagen content and structure or processed by immunohistochemistry to identify macrophages or nerve fibers. The census of macrophages and density of nerve fibers in the cervix peaked on day 21, the day before birth, and then declined post partum. These results replicate in time course and magnitude previous studies in mice. To address the main objective, the hypogastric nerve was bilaterally transected on day 15 post-breeding; sham-operated rats served as controls. Pups were born in both groups at normal term. Transection of the hypogastric nerves did not affect remodeling of collagen or the census of macrophages or the density of nerve fibers in the cervix. These findings support the contention that enhanced innervation and immigration of immune cells are associated with remodeling of the cervix and parturition, but that a neural pathway other than the hypogastric nerve may participate in the process of cervical ripening.

Randomized trial of preinduction cervical ripening: misoprostol vs oxytocin

OBJECTIVE

The purpose of this study was to compare the vaginal delivery rate in women who undergo labor induction with preinduction misoprostol or oxytocin alone.

STUDY DESIGN

Women with singleton pregnancies and Bishop scores <5 with labor induction at > or = 24 weeks of gestation were eligible; they were assigned randomly to oxytocin alone or preinduction cervical ripening with misoprostol. Labor characteristics, maternal complications, and neonatal outcomes were analyzed.

RESULTS

One hundred sixty-three women received oxytocin, and 164 women received misoprostol. Maternal demographics, pretreatment Bishop scores, and labor analgesia were similar between groups. Vaginal delivery rates were also similar: 87% (n = 141) for oxytocin and 81% (n = 133) for misoprostol. Mean time from treatment to delivery was shorter for the oxytocin group, compared with the misoprostol group (13.1 vs 16.3 hours; P = .005). There was no difference in maternal complications or neonatal outcomes between groups.

CONCLUSION

Preinduction cervical ripening with misoprostol did not improve the vaginal delivery rate and resulted in longer intervals to active labor and delivery. Preinduction cervical ripening with misoprostol may not be necessary.

Determining dose and endpoints of a controlled-release misoprostol vaginal insert for a phase III trial

OBJECTIVE

To determine phase III study design using the phase II data for a proprietary controlled-release misoprostol vaginal insert for cervical ripening and labor induction.

METHODS

The reported experiences in 2 phase II trials involving induction of labor in 168 women are discussed.

RESULTS

Combining data from 2 phase II studies, we reported a median induction to vaginal delivery interval of <15 hours regardless of parity using the 100-microg insert. This misoprostol vaginal insert was well tolerated with few maternal systemic effects. Uterine hyperstimulation occurred in <5% of cases in the 100-microg and lesser dose groups. Hyperstimulation syndrome attributed to insert led to cesarean delivery in 1 (2.4%) subject in the 200-microg and 2 (33.3%) in the 300-microg dose groups. The lowest cesarean rates were 4.7% (2 of 43) in the 100-microg group and 5.7% (2 of 35) in the 50-microg group.

CONCLUSION

Misoprostol vaginal 50-microg and 100-microg inserts had acceptable efficacy and safety profiles, and we agreed to test these doses in a randomized phase III multicenter study using dinoprostone (Cervidil, Forest Pharmaceuticals, St. Louis, Missouri), a dinoprostone vaginal insert, as the blinded comparator.

Selective use of sonographic cervical length measurement for predicting imminent preterm delivery in women with preterm labor and intact membranes

OBJECTIVES

To determine, in a population of women with preterm labor and intact membranes, whether ultrasound cervical length measurement performed only in patients selected according to the Bishop score predicts imminent preterm delivery better than does systematic cervical length measurement in the entire population.

METHODS

The Bishop score and sonographic cervical length were recorded prospectively in women with preterm labor between 24 and 34 completed weeks' gestation. Outcome measures were preterm delivery within 48 h and within 7 days. Predictive values were calculated for each marker separately and then in combination.

RESULTS

Of the study population of 395 women, 17 (4.3%) and 32 (8.1%) delivered within 48 h and within 7 days, respectively, following inclusion. For delivery within 7 days, areas under the Bishop score (0.848) and sonographic cervical length (0.813) receiver-operating characteristics curves did not differ significantly. For the selective use of sonographic cervical length measurement in patients selected according to the Bishop score, the test was considered positive if the Bishop score was >or= 8, or 4-7 with cervical length <or= 30 mm. This test was as sensitive (94%) but more specific (60% vs. 42%, P < 0.001) for predicting preterm birth within 7 days than was sonographic cervical length with a 30-mm cut-off value in the entire population. Results were similar for delivery within 48 h.

CONCLUSION

For predicting imminent preterm delivery in women with preterm labor, measuring sonographic cervical length only in patients with a Bishop score between 4 and 7, compared with a strategy of systematic measurement in the entire population, reduces by 30% the number of false positives and might thus decrease unnecessary therapeutic intervention.

Ultrasound assessment of cervical length in prolonged pregnancy: prediction of spontaneous onset of labor and successful vaginal delivery

OBJECTIVES

To evaluate the usefulness of sonographic assessment of cervical length in the prediction of spontaneous onset of labor and of vaginal delivery.

METHODS

Two hundred and six women who attended a dedicated postdates clinic at 41 + 3 weeks of pregnancy and agreed to the assessment of cervical length using transvaginal ultrasound imaging were included in the study. Those who had not delivered at 42 weeks were offered induction of labor. The labor details were recorded prospectively, and the onset of spontaneous labor and mode of delivery were correlated with cervical length data.

RESULTS

Women who underwent spontaneous onset of labor (n = 112) had a significantly shorter cervical length (mean (SD) 25.0 (8.3) mm) than had women whose labor was induced (n = 67; mean (SD) 29.7 (8.5) mm). Logistic regression analysis showed that cervical length was an independent predictor of the likelihood of spontaneous labor in nulliparous women, and of vaginal delivery in both nulliparous and parous women. Parity had no independent effect on the onset of spontaneous labor, but was an independent predictor of the likelihood of vaginal delivery.

CONCLUSIONS

Sonographic assessment of cervical length is a significant independent predictor of the likelihood of the onset of spontaneous labor in nulliparous women, and of successful vaginal delivery in both nulliparous and parous women with prolonged pregnancy.

Predictors of newborn admission after labour induction at term: Bishop score, pre-induction ultrasonography and clinical risk factors

INTRODUCTION

Following labour induction at term, 12 percent of neonates can expected to be admitted to the neonatal intensive care unit. We aimed to evaluate the Bishop score, pre-induction ultrasonography (US) assessment of amniotic fluid, foetal weight and cervical length, and pre-induction and intrapartum risk factors as predictors of neonatal admission.

METHODS

152 women at term, scheduled for labour induction, consented to participate in this prospective study. Transabdominal US was performed to obtain foetal biometry and amniotic fluid index, followed by transvaginal US to measure cervical length. US findings were concealed. The Bishop score was obtained at initiation of labour induction. Pre-induction and intrapartum risk factors were also considered in the multivariate logistic regression analysis. All study women received standard care.

RESULTS

On univariate analysis, factors associated with neonatal admission were: gestational age at less than or equal to 40 weeks, labour induction for diabetes mellitus, Bishop score of less than 5 at initiation of labour induction, estimated foetal weight of less than 2.5 kg by US, induction to delivery interval of more than 24 hours, caesarean delivery and umbilical cord blood pH of less than 7.1. Cervical length of greater than 20 mm on transvaginal US (p-value is 0.10) was not significant. After multivariate logistic regression analysis, controlling for the significant variables, only the unfavourable Bishop score (adjusted OR 4.2; 95% CI 1.2-13.8; p-value is 0.02) and caesarean delivery (adjusted OR 3.9; 95% CI 1.1-13.7; p-value is 0.035) were independent predictors of neonatal admission.

CONCLUSION

The identification of an unfavourable Bishop score as an independent predictor of neonatal admission is useful in the counselling of women who are considering labour induction.

A new insertion technique for the transcervical Foley catheter used for cervical ripening

OBJECTIVE

To describe a new placement technique for the transcervical Foley catheter that may succeed when other methods have failed.

STUDY DESIGN

Sixteen patients were identified as candidates for placement of a transcervical Foley catheter for cervical ripening, but all had failed attempted placement using the classically described methods. Our new placement technique involved the use of a 5 French rigid catheter guide inserted into the Foley catheter to make the catheter rigid and to ease insertion. RESLLTS: Placement was 100% successful in all 16 patients using the new insertion technique.

CONCLUSION

The use of a rigid stylet during insertion increases the chances of success. The ease of insertion using this technique makes the use of a Foley catheter for cervical ripening a valuable option.

Intracervical prostaglandins for induction of labour

BACKGROUND

Prostaglandins have been used for cervical ripening and induction of labour since the 1970s. The goal of the administration of prostaglandins in the process of induction of labour is to achieve cervical ripening before the onset of contractions. One of the routes of administration that was proposed is intracervical. Using this route, prostaglandins are less easy to administer and the need for exposing the cervix may cause discomfort to the woman.

OBJECTIVES

To determine the effects of intracervical prostaglandins for third trimester cervical ripening or induction of labour compared with placebo/no treatment and with vaginal prostaglandins (except misoprostol).

SEARCH STRATEGY

We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (August 2007) and bibliographies of relevant papers.

SELECTION CRITERIA

Clinical trials comparing intracervical prostaglandins used for third trimester cervical ripening or labour induction with placebo/no treatment or other methods listed above it on a predefined list of labour induction methods (vaginal prostaglandins, except misoprostol).

DATA COLLECTION AND ANALYSIS

A strategy was developed to deal with the large volume and complexity of trial data relating to labour induction. This involved a two-stage method of data extraction.

MAIN RESULTS

Fifty-six trials (7738 women) are included. INTRACERVICAL PGE2 WITH PLACEBO/NO TREATMENT: 28 TRIALS, 3764 WOMEN: Four studies reported the number of women who did not achieve vaginal delivery within 24 hours, showing a decreased risk with PGE2 (relative risk (RR) 0.61; 95% confidence interval (CI) 0.47 to 0.79). There was a small, and statistically non-significant, reduction of the risk of caesarean section when PGE2 was used (RR 0.88; 95% CI 0.77 to 1.00). The finding was statistically significant in a subgroup of women with intact membranes and unfavourable cervix only (RR 0.82; 95% CI 0.68 to 0.98). The risk of hyperstimulation with fetal heart rate (FHR) changes was not significantly increased (RR 1.21; 95% CI 0.72 to 2.05). However, the risk of hyperstimulation without FHR changes was significantly increased (RR 1.59; 95% CI 1.09 to 2.33. INTRACERVICAL PGE2 WITH INTRAVAGINAL PGE2: 29 TRIALS, 3881 WOMEN: The risk of not achieving vaginal delivery within 24 hours was increased with intracervical PGE2 (RR 1.26; 95% CI 1.12 to 1.41). There was no change in the risk of caesarean section (RR 1.07; 95% CI 0.93 to 1.22). The risks of hyperstimulation with FHR changes (RR 0.76; 95% CI 0.39 to 1.49) and without FHR changes (RR 0.80; 95% CI 0.56 to 1.15) were non-significantly different with the two methods of PGE2 administration. Only one trial with small sample size reported on women's views, with no difference between groups. INTRACERVICAL PGE2 LOW DOSE WITH INTRACERVICAL PGE2 HIGH DOSE: TWO TRIALS, 102 WOMEN: The trials are too small to provide any useful information.

AUTHORS' CONCLUSIONS

Intracervical prostaglandins are effective compared to placebo, but appear inferior when compared to intravaginal prostaglandins.

Frequency domain near-infrared spectroscopy of the uterine cervix during cervical ripening

OBJECTIVE

Preterm labor is a common obstetric complication. Clinical evaluation of cervical ripening to predict preterm labor has a substantial inter- and intraobserver variability. We used frequency domain near-infrared spectroscopy (FD-NIRS) to non-invasively investigate the changes of the optical properties (i.e., absorption and scattering of light) in the uterine cervix during drug-induced cervical ripening.

METHODS

Ten volunteers scheduled for abortion were examined. Optical properties of the uterine cervix were measured and physiological parameters were calculated prior to and after induction of cervical ripening using topical misoprostol. Mean relative changes, +/-standard error of the mean as well as statistical significance using the t-test were calculated for oxy- and deoxyhemoglobin, total hemoglobin, oxygen-saturation, and water. The wavelength-dependent decrease of scattering (scatter power) was calculated by an exponential fit and tested with the Wilcoxon test.

RESULTS

Misoprostol induced a decrease in total hemoglobin of 21 +/- 6% (P < 0.05), a decrease in oxyhemoglobin of 22 +/- 6% (P < 0.05), a decrease in deoxyhemoglobin of 16 +/- 11% and an increase of 36 +/- 8% (P < 0.005) in water content. The scatter power was significantly lower (P < 0.05) after cervical ripening.

CONCLUSION

Our results show that FD-NIRS is a promising diagnostic tool to detect changes in cervical concentrations of hemoglobin and water. A severe tissue edema, probably due to a hormone-induced inflammatory process, seems to be important for cervical ripening. The reduction in total hemoglobin is likely to be a consequence of the increased water content of the tissue resulting in a dramatic increase of the distance between vessels. We propose this technology to assess the cervical ripening and eventually to predict preterm labor.