Prediction of the risk of cesarean delivery after labor induction in twin gestations based on clinical and ultrasound parameters

AIMS

To develop a model based on clinical and ultrasound parameters to predict the risk of cesarean delivery after labor induction in near-term twin gestations.

METHODS

This retrospective cohort study included 189 consecutive women with twin gestations at ≥ 36.0 weeks scheduled for labor induction. The Bishop score and transvaginal ultrasonographic measurements of cervical length were obtained immediately before labor induction. Parameters studied included maternal age, height, weight, parity, gestational age, Bishop score, cervical length, epidural analgesia, method of conception, chorionicity and birth weight. Prostaglandin E2 (dinoprostone) and oxytocin were used for labor induction. Logistic regression analysis and receiver operating characteristic curve were used to generate a predictive model for cesarean delivery.

RESULTS

Fifty (26.5%) of the 189 women had cesarean deliveries. According to logistic regression analysis, maternal height (P = 0.004), parity (P = 0.005) and cervical length (P = 0.016), but not Bishop score (P = 0.920), were identified as independent predictors of cesarean delivery. A risk score based on a model of these three parameters was calculated for each patient. The model was shown to have an adequate goodness of fit (P = 0.201) and the area under the curve was 0.722, indicating fairly good discrimination.

CONCLUSIONS

Maternal height, parity and cervical length were independent parameters for predicting the risk of cesarean delivery after labor induction in twin gestations. A predictive model using these parameters may provide useful information for deciding whether or not to induce labor.

Uterine artery embolization, not cesarean section, as an option for termination of pregnancy in placenta previa

OBJECTIVE

To summarize our experiences in the treatment of labor induction in placenta previa using uterine artery embolization.

CASE REPORT

We retrospectively analyzed the clinical data of seven patients with placenta previa who underwent antepartum uterine artery embolization before vaginal delivery. After antepartum embolization, five patients with placenta previa had successful vaginal deliveries and two cases of placenta previa with accreta underwent emergency hysterectomy. Some complications were reported in this experience. The follow-up study showed that most patients resumed their normal menstruation and some of them were able to conceive.

CONCLUSION

For the management of placenta previa, uterine artery embolization is a minimally invasive technique that helps to avoid cesarean section. The impact on menstruation and fertility is yet to be seen.

Cervical condition and fetal cerebral Doppler as determinants of adverse perinatal outcome after labor induction for late-onset small-for-gestational-age fetuses

OBJECTIVE

To estimate the combined value of fetal cerebral Doppler examination and Bishop score for predicting perinatal outcome after labor induction for small-for-gestational-age (SGA) fetuses in the presence of normal umbilical artery Doppler recordings.

METHODS

We conducted a cohort study in two tertiary centers, including 164 women with normal umbilical artery Doppler recordings who underwent induction of labor because of an estimated fetal weight < 10(th) percentile. The fetal middle cerebral artery pulsatility index and cerebroplacental ratio (CPR) were obtained in all cases within 24 h before induction. Cervical condition was assessed at admission using the Bishop score. A predictive model for perinatal outcomes was constructed using a decision-tree analysis algorithm.

RESULTS

Both a very unfavorable cervix, defined as a Bishop score < 2, (odds ratio (OR), 3.18; 95% CI, 1.28-7.86) and an abnormal CPR (OR, 2.54; 95% CI, 1.18-5.61) were associated with an increased likelihood of emergency Cesarean section for fetal distress, but only the latter was significantly associated with the need for neonatal admission (OR, 2.43; 95% CI, 1.28-4.59). In the decision-tree analysis, both criteria significantly predicted the likelihood of Cesarean section for fetal distress.

CONCLUSION

Combined use of the Bishop score and CPR improves the ability to predict overall Cesarean section (for any indication), emergency Cesarean section for fetal distress, and neonatal admission after labor induction for late-onset SGA in the presence of normal umbilical artery Doppler recordings.

Delivery planning for pregnancies with gastroschisis: findings from a prospective national registry

OBJECTIVE

The purpose of this study was to determine the influence of planned mode and planned timing of delivery on neonatal outcomes in infants with gastroschisis.

STUDY DESIGN

Data from the Canadian Pediatric Surgery Network cohort were used to identify 519 fetuses with isolated gastroschisis who were delivered at all tertiary-level perinatal centers in Canada from 2005-2013 (n = 16). Neonatal outcomes (including length of stay, duration of total parenteral nutrition, and a composite of perinatal death or prolonged exclusive total parenteral nutrition) were compared according to the 32-week gestation planned mode and timing of delivery with the use of the multivariable quantile and logistic regression.

RESULTS

Planned induction of labor was not associated with decreased length of stay (adjusted median difference, -2.6 days; 95% confidence interval [CI], -9.9 to 4.8), total parenteral nutrition duration (adjusted median difference, -0.2 days; 95% CI, -6.4 to 6.0), or risk of the composite adverse outcome (relative risk, 1.7; 95% CI, 0.1-3.2) compared with planned vaginal delivery after spontaneous onset of labor. Planned delivery at 36-37 weeks' gestation was not associated with decreased length of stay (adjusted median difference, 5.9 days; 95% CI, -5.7 to 17.5), total parenteral nutrition duration (adjusted median difference, 3.2 days; 95% CI, -7.9 to 14.3), or risk of composite outcome (relative risk, 2.3; 95% CI, 0.8-5.4) compared with planned delivery at ≥38 weeks' gestation.

CONCLUSION

Infants with gastroschisis who were delivered after planned induction or planned delivery at 36-37 weeks' gestation did not have significantly better neonatal outcomes than planned vaginal delivery after spontaneous onset of labor and planned delivery at ≥38 weeks' gestation.

Induction of labor in the obese patient

Obese women are at an increased risk of antepartum pregnancy complications and are therefore more likely to require an induction of labor than normal weight women. They also have an increased rate of failing an induction of labor, a rate that rises significantly with increasing body mass index, and subsequent surgical and neonatal complications of an intrapartum cesarean delivery. This increase in induction failure may be due to differences in the myometrium of obese women resulting in decreased contraction strength. There have been only a few studies comparing the efficacy of the various cervical ripening agents in obese women and at this point no recommendation can be made as to what method may result in the greatest chance of a successful induction.

Controlled-release dinoprostone insert versus Foley catheter for labor induction: a meta-analysis

OBJECTIVE

To compare the effectiveness and safety of controlled-release dinoprostone insert with Foley catheter balloon for cervical ripening and labor induction.

METHODS

PubMed, Cochrane Central Register of Controlled Trials, Web of Science, and China Knowledge Resource Integrated Database were searched. Only randomized controlled trials comparing controlled-release dinoprostone insert with Foley catheter balloon were included. Risk ratio (RR) or mean difference (MD) with 95% confidence interval (CI) was calculated.

RESULTS

Six studies were included with 731 women received dinoprostone insert and 722 Foley catheter. Time from induction to delivery was significantly shortened in dinoprostone insert group compared to Foley catheter group (MD 5.73 h, 95% CI 1.26-10.20). There were no significant differences in vaginal delivery within 24 h (RR 0.75, 95% CI 0.43-1.30) or cesarean section (RR 0.94, 95% CI 0.80-1.12) between two ripening methods. Dinoprostone insert was related with increased rate of excessive uterine contraction (RR 0.07, 95% CI 0.03-0.19), but less oxytocin use (RR 1.86, 95% CI 1.25-2.77) when compared with Foley catheter.

CONCLUSIONS

Induction of labor with controlled-release dinoprostone insert seems to be more effective than Foley catheter. However, the former method causes excessive uterine contraction more frequently.

Failed induction of labor

Induction of labor will affect almost a quarter of all pregnancies, but historically there has been no generally accepted definition of failed induction of labor. Only recently have studies analyzed the lengths of latent labor that are associated with successful labor induction ending in a vaginal delivery, and recommendations for uniformity in the diagnosis of failed induction have largely resulted from this data. This review assesses the most recent and inclusive definition for failed induction, risk factors associated with failure, complications, and special populations that may be at risk for a failed induction.

Patient-Perceived Pressure from Clinicians for Labor Induction and Cesarean Delivery: A Population-Based Survey of U.S. Women

OBJECTIVE

To determine whether patient-perceived pressure from clinicians for labor induction or cesarean delivery is significantly associated with having these procedures.

DATA SOURCES/STUDY SETTING

Listening to Mothers III, a nationally representative survey of women 18-45 years who delivered a singleton infant in a U.S. hospital July 2011-June 2012 (N = 2,400).

STUDY DESIGN

Multivariate logistic regression analysis of factors associated with perceived pressure and estimation of odds of induction and cesarean given perceived pressure.

PRINCIPAL FINDINGS

Overall, 14.8 percent of respondents perceived pressure from a clinician for labor induction and 13.3 percent for cesarean delivery. Women who perceived pressure for labor induction had higher odds of induction overall (adjusted odds ratio [aOR]: 3.51; 95 percent confidence interval [CI]: 2.5-5.0) and without medical reason (aOR: 2.13; 95 percent CI: 1.3-3.4) compared with women who did not perceive pressure. Those perceiving pressure for cesarean delivery had higher odds of cesarean overall (aOR: 5.17; 95 percent CI: 3.2-8.4), without medical reason (aOR: 6.13; 95 percent CI: 3.4-11.1), and unplanned cesarean (aOR: 6.70; 95 percent CI: 4.0-11.3).

CONCLUSIONS

Patient-perceived pressure from clinicians significantly predicts labor induction and cesarean delivery. Efforts to reduce provider-patient miscommunication and minimize potentially unnecessary procedures may be warranted.

Investigating racial differences in risk factors for primary cesarean delivery

OBJECTIVE

The objective of the study was to investigate differences in sociodemographic, medical, and obstetric risk factors for primary cesarean delivery between black and white women.

STUDY DESIGN

We conducted a retrospective cohort study among 25,251 black and white women delivering a live, singleton infant with vertex presentation at a large, regional hospital between 2004 and 2010. Demographic and clinical data were derived from electronic hospital records. Differences in risk factors for primary cesarean delivery were analyzed using a modified Poisson regression approach stratified by race and parity.

RESULTS

Black and white women had a primary cesarean delivery rate of 24.7% and 22.2%, respectively (P < .001). Black women had an increased risk of cesarean delivery after adjusting for sociodemographic and clinical risk factors (adjusted relative risk [RR], 1.23; 95% confidence interval [CI], 1.17-1.29). Among nulliparas, labor induction had a greater effect on cesarean delivery for black women (adjusted RR, 1.32; 95% CI, 1.20-1.44) than for white women (adjusted RR, 1.13; 95% CI, 1.07-1.20). Among multiparas, labor induction reduced the risk of cesarean delivery for white women (adjusted RR, 0.63; 95% CI, 0.55-0.72), whereas no association was observed for black women (adjusted RR, 1.08; 95% CI, 0.92-1.28). Advanced maternal age was a stronger risk factor for black women (adjusted RR, 1.72; 95% CI, 1.43-2.08) than for white women (adjusted RR, 1.30; 95% CI, 1.11-1.52) among multiparas only. Among nulliparas, delivery at 37-38 weeks' gestation reduced the risk of cesarean delivery for black women (adjusted RR, 0.82; 95% CI, 0.73-0.92), whereas no association was observed for white women (adjusted RR, 0.96; 95% CI, 0.90-1.04).

CONCLUSION

Labor induction, among nulliparous women, and advanced maternal age, among multiparous women, are stronger risk factors for primary cesarean delivery for black women than for white women.

Clinical utility of third-trimester uterine artery Doppler in the prediction of brain hemodynamic deterioration and adverse perinatal outcome in small-for-gestational-age fetuses

OBJECTIVE

To assess the clinical value of third-trimester uterine artery (UtA) Doppler ultrasound in the prediction of hemodynamic deterioration and adverse perinatal outcome in term small-for-gestational-age (SGA) fetuses.

METHODS

UtA Doppler parameters, cerebroplacental ratio (CPR) and fetal middle cerebral artery (MCA) pulsatility index (PI) were evaluated weekly, starting from the time of SGA diagnosis until 24 h before induction of labor, in a cohort of 327 SGA fetuses with normal umbilical artery PI (< 95th centile), delivered at > 37 weeks' gestation. Differences in the sequence of CPR and MCA-PI changes < 5th centile, between the group with normal UtA Doppler indices at diagnosis and those with abnormal UtA indices, were analyzed by survival analysis. In addition, the use of UtA Doppler value, alone or in combination with a brain Doppler scan before delivery, to predict the risk of Cesarean section, Cesarean section for non-reassuring fetal status (NRFS), neonatal acidosis and neonatal hospitalization was evaluated by logistic regression analysis, adjusted for gestational age at birth and birth-weight percentile.

RESULTS

Abnormal UtA Doppler at diagnosis of SGA was associated with a higher risk of developing abnormal brain Doppler indices before induction of labor than in those with a normal UtA at diagnosis (62.7% vs 34.6%, respectively; P < 0.01). Compared to those with normal UtA Doppler indices, those with abnormal UtA Doppler findings were associated with a higher risk of intrapartum Cesarean section (52.2% vs 37.3%, respectively; P = 0.03), Cesarean section for NRFS (35.8% vs 23.1%, respectively; P = 0.03), neonatal acidosis (10.4% vs 7.7%, respectively; P = 0.47) and neonatal hospitalization (23.9% vs 16.5%, respectively; P = 0.16). Logistic regression analysis indicated that UtA Doppler findings were not significantly associated with adverse perinatal outcome independent of brain Doppler findings.

CONCLUSION

UtA Doppler indices predict adverse perinatal outcome, but do not help to improve the predictive value of brain Doppler indices. However, at the time of SGA diagnosis they identify the subgroup of fetuses at highest risk of progression to abnormal brain Doppler findings.

Comparing vaginal misoprostol versus Foley catheter plus vaginal isosorbide mononitrate for labor induction

OBJECTIVE(S)

To compare the effectiveness and safety of intra-cervical Foley catheter combined with intra-vaginal isosorbide mononitrate (IMN) versus intra-vaginal misoprostol for cervical ripening and labor induction in pregnant women with unripe cervices.

METHODS

Open-labeled randomized controlled trial in Cairo university hospital, Cairo, Egypt during 2012-2014. Three hundred and ninety-five pregnant women at term or post-term with an indication for labor induction and unripe cervix were included in the study. The subjects were randomly divided into two groups. Vaginal misoprostol was used in group 1 (n = 197) and intra-cervical Foley catheter plus vaginal IMN in group 2 (n = 198). Our main outcome measure was cesarean section rate.

RESULTS

Among the 395 included patients there were significantly lower duration of induction of labor (p < 0.001) in group 1with lower cesarean section rates [22.8% in group 1versus 33.3% in group 2; RR 0.7 (0.6-0.9), (p = 0.020)]. Whereas the uterine hyperstimulation (p < 0.001) was significantly higher in group 1. There were no significant differences between both groups as regard patients' demographic characteristics.

CONCLUSIONS(S)

Vaginal misoprostol is more effective but less safe than Foley catheter combined with vaginal IMN for induction of labor in term and post-term pregnancy.

Spontaneous delivery through a cervical tear without cervical os dilatation

Spontaneous delivery through a cervical tear, provoked by prostaglandin-induced uterine contractions, was described in a G2P0 woman with a history of cervical dilatation and uterine curettage. This rare complication with potentially serious maternal–fetal consequences can be predicted by an aberrant cervical response to prostaglandins in parturients with previous cervical interventions.

Evaluation effect of shiatsu technique on labor induction in post-term pregnancy

OBJECTIVES

Labor induction in post-term pregnancy is considered as a conventional process of mothers' care. Shiatsu technique is one of the complementary methods which use for post-term pregnancy induction. Therefore, the researchers decided to examine the effect of Shiatsu technique on the induction of post-term pregnancy.

MATERIALS & METHODS

This is a randomized control trials which conducted on 288 women with post-term pregnancy who referred to consulting clinic at Ali- Ibn- Abi -Talib Hospital, in Zahedan-Iran in 2010-2011. Participants were selected based on random table. The participants divided into two groups: the first was shiatsu technique and the second group was control group (routine procedure). Shiatsu technique was conducted on the participants of intervention group for 30s on three points by an experienced midwife. The gathered data analyzed by SPSS version 15.00 and comparing tests were t-students tests, chi-square.

RESULTS

Mothers ages range were between 16 to 42 years (mean 26.5-5.7) in shiatsu and 17 to 43 years (mean 24.5-5.1) in control group. Regarding spontaneous initiation of labor, 82 women (56.9%) in Shiatsu group had spontaneous initiation of labor, whereas the number of women was only 12 (8.3%) in control group. Women who have used Shiatsu technique were significantly more likely to have spontaneous labour than those women who did not.

CONCLUSIONS

Results of the study showed that shiatsu technique can be used as one of safe complementary methods for post-term pregnancy induction.

Factors associated with higher oxytocin requirements in labor

OBJECTIVE

To identify clinical characteristics associated with high maximum oxytocin doses in women who achieve complete cervical dilation.

METHODS

A retrospective nested case-control study was performed within a cohort of all term women at a single center between 2004 and 2008 who reached the second stage of labor. Cases were defined as women who had a maximum oxytocin dose during labor >20 mu/min, while women in the control group had a maximum oxytocin dose during labor of ≤20 mu/min. Exclusion criteria included no oxytocin administration during labor, multiple gestations, major fetal anomalies, nonvertex presentation, and prior cesarean delivery. Multiple maternal, fetal, and labor factors were evaluated with univariable analysis and multivariable logistic regression.

RESULTS

Maximum oxytocin doses >20 mu/min were administered to 108 women (3.6%), while 2864 women received doses ≤20 mu/min. Factors associated with higher maximum oxytocin dose after adjusting for relevant confounders included maternal diabetes, birthweight >4000 g, intrapartum fever, administration of magnesium, and induction of labor.

CONCLUSIONS

Few women who achieve complete cervical dilation require high doses of oxytocin. We identified maternal, fetal and labor factors that characterize this group of parturients.

Can measurement of cervical length, fetal head position and posterior cervical angle be an alternative method to Bishop score in the prediction of successful labor induction?

AIM

The purpose of this study was to evaluate sonographic cervical length, posterior cervical angle and fetal head position in predicting successful induction of labor at term can be an alternative method to Bishop score.

METHODS

This prospective observational study recruited 223 women with singleton gestations scheduled for induction of labor at 37-42 weeks. Parity, body mass index, Bishop score, fetal head position, cervical angle measurement and cervical length was investigated to predict successful labor induction. Multiple regression analysis was performed to determine the parameters in the prediction of successful vaginal delivery within 24 hours.

RESULTS

Forty-five patients were excluded because of cesarean section performed for other reasons than arrest of dilation or fetal head descent (43 fetal distress, 2 cord prolapsus). Remaining 178 patients were divided into two groups according to duration of delivery time. 139 patients delivered within 24 hours were classified as group I, 39 patients delivered after 24 hours were classified as group II. Percentage of multiparity was statistically significantly higher in group I than in group II [59 (42.4%), 9 (23.0%) respectively, p = 0.009]. Cervical length was statistically significantly shorter in group I than in group II [23.1 ± 7.42 mm, 31.3 ± 6.83 mm respectively, p < 0.001]. Bishop score was statistically significantly higher in group I than in group II [3 (1-4), 1 (1-4) respectively, p < 0.001]. Posterior cervical angle was statistically significantly higher in group I than in group II [100.1 ± 17.2, 92.7 ± 21.4 respectively, p = 0.007]. According to the fetal head position, there was no statistically significant difference in labor duration between the groups (p = 0.787). In the multivariate regression analysis of variables, multiparity, cervical length and Bishop score were statistically significantly predictive in successful labor induction.

CONCLUSION

Multiparity status, cervical length, posterior cervical angle and Bishop score can predict successful labor induction, but fetal head position is not predictive in successful labor induction.

Trans-cervical double balloon catheter with and without extra-amniotic saline infusion for cervical ripening: a prospective quasi-randomized trial

OBJECTIVE

To compare the efficacy and safety of the trans-cervical double balloon catheter with and without extra-amniotic saline infusion (EASI) for cervical ripening.

METHODS

This is a secondary analysis of a prospective randomized study conducted between November 2007 and January 2011 evaluating different ripening methods. Women presenting for labor induction were assigned to receive the double balloon catheter with (study group) or without EASI (control group). Outcomes included time from device insertion to delivery, cesarean section rates, and adverse events.

RESULTS

One hundred and sixty women completed the study. Cesarean section rate (8.3% in study group, versus 20% in controls p = 0.07) and ripening success were comparable between the groups. Catheter insertion to delivery interval was significantly shorter and spontaneous catheter expulsion rate was significantly higher in the study group (14:19 hours versus 20:45 hours, p < 0.001, and 68.5% versus 51%, p = 0.04, respectively). Hospitalization length was significantly shorter in the study arm. There were no differences in other outcomes evaluated. A multivariable analysis found the EASI to be an independent predictor of a shorter insertion to delivery interval.

CONCLUSIONS

The addition of EASI to the double balloon catheter for cervical ripening results in a shorter labor induction process without compromising its safety.

Induction of labor in twin pregnancies with oral misoprostol versus vaginal dinoprostone--is it effective and safe?

OBJECTIVE

To compare the effectiveness and safety of oral misoprostol versus vaginal dinoprostone for the induction of labor in twin pregnancies.

METHODS

All twin pregnancies ≥ 34 weeks 0 days that were induced with either misoprostol or dinoprostone in St. Hedwig Hospital between 2002 and 2013 were included in this retrospective study. Length of induction, mode of delivery, maternal and neonatal outcomes were compared between the two groups.

RESULTS

After identifying 186 twin mothers matching the inclusion criteria, 154 women were induced with misoprostol (group A) and 32 with dinoprostone (group B). There were no differences in demographic data between the groups. Rates of successful vaginal delivery (53.9% versus 56.3%) and length of induction to delivery (30.2 h versus 26.9 h) were also similar. There were slightly higher rates of postpartum hemorrhage in group B (16.6% versus 10.8%), but without reaching statistical significance. Neonatal outcomes regarding umbilical artery pH <7.20 and one minute Apgar also were without significant differences.

CONCLUSIONS

Study data indicate that oral misoprostol and vaginal dinoprostone are similarly effective and safe for the induction of labor in twin gestations. Further trials with larger series are needed to confirm these results.

Trends in childbirth before 39 weeks' gestation without medical indication

BACKGROUND

There is increasing attention to labor induction and cesarean delivery occurring at 37 0/7-38 6/7 weeks' gestation (early-term) without medical indication.

OBJECTIVE

To measure prevalence, change over time, patient characteristics, and infant outcomes associated with early-term nonindicated births.

RESEARCH DESIGN AND SUBJECTS

Retrospective analysis using linked hospital discharge and birth certificate data for the 7,296,363 uncomplicated births (>37 0/7 wk' gestation) between 1995 and 2009 in 3 states.

MEASURES

Early-term nonindicated birth is calculated using diagnosis codes and birth certificate records. Secondary outcomes included infant prolonged length of stay and respiratory distress.

RESULTS

Across uncomplicated term births, the early-term nonindicated birth rate was 3.18%. After adjustment, the risk of nonindicated birth before 39 0/7 weeks was 86% higher in 2009 than in 1995 [hazard ratio (HR)=1.86; 95% confidence interval (CI), 1.81-1.90], peaking in 2006 (HR=2.03; P<0.001). Factors independently associated with higher odds included maternal age, higher education levels, private health insurance, and delivering at smaller-volume or nonteaching hospitals. Black women had higher risk of nonindicated cesarean birth (HR=1.29; 95% CI, 1.27-1.32), which was associated with greater odds of prolonged length of stay [adjusted odds ratio (AOR)=1.60; 95% CI, 1.57-1.64] and infant respiratory distress (AOR=2.44; 95% CI, 2.37-2.50) compared with births after 38 6/7 weeks. Early-term nonindicated induction was also associated with comparatively greater odds of prolonged length of stay (AOR=1.20; 95% CI, 1.17-1.23).

CONCLUSIONS

Nearly 4% of all uncomplicated births to term infants occurred before 39 0/7 weeks' gestation without medical indication. These births were associated with adverse infant outcomes.

Interrelations between four antepartum obstetric interventions and cesarean delivery in women at low risk: a systematic review and modeling of the cascade of interventions

OBJECTIVES

To critically appraise the literature on the relations between four intrapartum obstetric interventions-electronic fetal monitoring (EFM), epidural analgesia, labor induction, and labor acceleration; and two types of delivery-instrumental (forceps and vacuum) and cesarean section.

METHODS

This review included meta-analyses published between January 2000 and April 2012 including at least one randomized clinical trial published after 1995 and presenting results on low-risk pregnancies between 37 and 42 weeks of gestation, searched in the databases Medline, Cochrane Library, and EMBASE with no language restriction.

RESULTS

Of 306 documents identified, 8 fulfilled the inclusion criteria and presented results on women at low risk. EFM at admission (vs intermittent auscultation) was associated with cesarean delivery (odds ratio [OR] = 1.20, 95% confidence interval [CI] 1.00-1.44) and epidural analgesia (OR = 1.25, 95% CI 1.09-1.43). Epidural on request was associated with cesarean delivery (OR = 1.60, 95% CI 1.18-2.18), instrumental delivery (OR = 1.21, 95% CI 1.03-1.44), and oxytocin use (OR = 1.20, 95% CI 1.01-1.43) when compared with epidural on request plus nonpharmacological labor pain control methods such as one-to-one support, breathing techniques, and relaxation. Induction and acceleration of labor showed heterogeneous patterns of associations with cesarean delivery and instrumental delivery.

CONCLUSIONS

Complex patterns of associations between obstetric interventions and modes of delivery were illustrated in an empirical model. Intermittent auscultation and nonpharmacological labor pain control interventions, such as one-to-one support during labor, have the potential for substantially reducing cesarean deliveries.

Making cervical ripening EASI: a prospective controlled comparison of single versus double balloon catheters

OBJECTIVE

To compare the efficacy of two mechanical devices for cervical ripening: double versus single balloon catheters, both with extra-amniotic saline infusion (EASI).

METHODS

Women at term with a singleton pregnancy presenting for labor induction were assigned to receive the double balloon catheter (with EASI) or the single balloon catheter (with EASI). Outcomes included time from device insertion to delivery, rates of successful vaginal delivery and occurrence of adverse events.

RESULTS

One hundred and eighty-six women completed the study. Ripening success was comparable between the double and single balloon arms (96.4% versus 92.7%, p = 0.55, respectively). Balloon insertion to delivery interval was significantly shorter, and cesarean section rate was significantly lower in the double balloon arm compared with the single balloon arm (14.3 versus 15.8 h, p = 0.04 and 8.3% versus 20%, p = 0.05, respectively). There were no significant differences in maternal characteristics, satisfaction or adverse outcomes.

CONCLUSIONS

This study is the first documented assessment of the double balloon catheter combined with EASI. Our findings suggest that the double balloon catheter results in reduced time to delivery and higher vaginal delivery rates, compared with the single balloon catheter with EASI, without compromising maternal or fetal safety.

Healthy birth practice #1: let labor begin on its own

As cesarean rates have climbed to almost one-third of all births in the United States, current research and professional organizations have identified letting labor begin on its own as one of the most important strategies for reducing the primary cesarean rate. At least equally important, letting labor begin on its own supports normal physiology, prevents iatrogenic prematurity, and prevents the cascade of interventions caused by labor induction. This article is an updated evidence-based review of the "Lamaze International Care Practices That Promote Normal Birth, Care Practice #1: Let Labor Begin on Its Own," published in The Journal of Perinatal Education, 16(3), 2007.

Use of nonmedical methods of labor induction and pain management among U.S. women

BACKGROUND

There exists limited documentation of nonmedical methods of labor induction and pain management during childbirth in the United States. We estimated the prevalence of nonmedical interventions for induction and pain management and examined the association between medical and nonmedical care during labor.

METHODS

We used a nationally representative survey of U.S. women who gave birth in 2005 (N = 1,382) to examine use of nonmedical methods of labor induction and pain management. Using logistic regression, we calculated odds of nonmedical and medical interventions to induce labor or mitigate pain, and the odds of medical induction and obstetric analgesia by whether nonmedical methods were reported.

RESULTS

Nearly 30 percent of women used nonmedical methods to start labor, and over 70 percent of women used nonmedical pain management. Doula support was the strongest predictor of nonmedical methods of labor induction (Adjusted Odds Ratio [AOR] = 3.0) and labor pain management (AOR = 5.7). Use of nonmedical pain management was significantly associated with decreased odds of medical pain management (OR = 0.65); this relationship was attenuated with covariate adjustment.

CONCLUSIONS

Nonmedical methods to induce labor and manage pain during childbirth are commonly used by U.S. women. Future research should examine effectiveness of these strategies and their influence on medical services use.

Progress of labor in women induced with misoprostol versus the Foley catheter

OBJECTIVE

To estimate and compare the duration and progress of labor in women induced with misoprostol vs Foley catheter plus oxytocin.

STUDY DESIGN

We performed a retrospective cohort study of labor progress among 617 consecutive term pregnancies induced with misoprostol (n = 503) or Foley catheter plus oxytocin (n = 114) who completed the first stage of labor. Labor duration and progress in the entire cohort, and stratified by parity, were compared in multivariable interval-censored regression models adjusting for maternal obesity and birthweight. Repeated-measures analysis with 9th degree polynomial modeling was used to construct average labor curves.

RESULTS

Total duration of labor was not significantly different in women induced with misoprostol compared with the Foley catheter (median duration from 1 to 10 cm: 12 vs 14.2 hours, P = .19). Progress from 1 to 4 cm was more rapid with the Foley catheter (median: 3.4 vs 5.6 hours, P < .01), although progress from 4 to 10 cm was slower (median: 6.3 vs 3.6 hours, P < .01). Labor curves demonstrated transition from latent to active labor at about 4 cm cervical dilatation with misoprostol and at 6 cm for the Foley catheter. Similar general patterns were noted for nulliparous and multiparous women, except for a shorter duration of labor with the Foley catheter among multiparous women.

CONCLUSION

Induction of labor with the Foley catheter is associated with more rapid initial cervical dilation, but transition to active labor occurs later compared with misoprostol. These differences should be considered in the management of induced labor.

Gestational age-specific severe maternal morbidity associated with labor induction

OBJECTIVE

The purpose of this study was to examine the association between labor induction and gestational age-specific severe maternal morbidity.

STUDY DESIGN

Our study was restricted to women who delivered singletons at 37-42 weeks' gestation who had no pregnancy complications from 2003-2010 (n = 1,601,253) in Canada (excluding Quebec). Using a pregnancies-at-risk approach, the week-specific rates of specific morbidity after induction were contrasted with rates among ongoing pregnancies. Logistic regression was used to adjust for confounders.

RESULTS

Induction increased the rate of postpartum hemorrhage that required blood transfusion at 38 weeks' gestation (adjusted rate ratio, 1.28; 95% confidence interval, 1.11-1.49) and 39 weeks' gestation (adjusted rate ratio, 1.21; 95% confidence interval, 1.06-1.38). Induction was also associated with higher rates of pueperal sepsis at 38 and 39 weeks' gestation and venous thromboembolism at 38 weeks' gestation. The absolute increase in morbidity rates was small; the number needed to harm was large (eg, 1270 for postpartum hemorrhage with blood transfusion at 38 weeks' gestation).

CONCLUSION

Among women without pregnancy complications, induction at earlier term is associated with higher rates of specific severe maternal morbidity, although absolute risks are low.

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.