The effect of epidural analgesia on labor progress and outcome in nulliparous women

Inconsistent definitions of prolonged labor in international literature: a scoping review

Objective

Prolonged labor is the commonest indication for intrapartum cesarean section, but definitions are inconsistent and some common definitions were recently found to overestimate the speed of physiological labor. The objective of this review is to establish an overview of synonyms and definitions used in the literature for prolonged labor, separated into first and second stages, and establish types of definitions used.

Data sources

A systematic search was conducted in PubMed, Embase, Web of Science, Cochrane Library, Emcare, and Academic Search Premier.

Study eligibility criteria

All articles in English that (1) attempted to define prolonged labor, (2) included a definition of prolonged labor, or (3) included any synonym for prolonged labor, were included.

Methods

Data on study design, year of publication, country or region of origin, synonyms used, definition of prolonged first and/or second stage, and origin of provided definition (if not primarily established by the study) were collected into a database.

Results

In total, 3402 abstracts and 536 full-text papers were screened, and 232 papers were included. Our search established 53 synonyms for prolonged labor. Forty-three studies defined prolonged labor and 189 studies adopted a definition of prolonged labor. Definitions for prolonged first stage of labor were categorized into: time-based (n=14), progress-based (n=12), clinician-based (n=5), or outcome-based (n=4). For the 33 studies defining prolonged second stage, the majority of definitions (n=25) were time-based, either based on total duration or duration of no descent of the presenting part.

Conclusions

Despite efforts to arrive at uniform labor curves, there is still little uniformity in definitions of prolonged labor. Consensus on which definition to use is called for, in order to safely and respectfully allow physiological labor progress, ensure timely management, and assess and compare incidence of prolonged labor between settings.

Oxytocin Administration in Low-Risk Women, a Retrospective Analysis of Birth and Neonatal Outcomes

BACKGROUND

In recent years, higher than the recommended rate of oxytocin use has been observed among low-risk women. This study examines the relationship between oxytocin administration and birth outcomes in women and neonates.

METHODS

A retrospective analysis of birth and neonatal outcomes for women who received oxytocin versus those who did not. The sample included 322 women with a low-risk pregnancy.

RESULTS

Oxytocin administration was associated with cesarean section (aOR 4.81, 95% CI: 1.80-12.81), instrumental birth (aOR 3.34, 95% CI: 1.45-7.67), episiotomy (aOR 3.79, 95% CI: 2.20-6.52) and length of the second stage (aOR 00:18, 95% CI: 00:04-00:31). In neonatal outcomes, oxytocin in labor was associated with umbilical artery pH ≤ 7.20 (OR 3.29, 95% CI: 1.33-8.14). Admission to neonatal intensive care unit (OR 0.56, 95% CI: 0.22-1.42), neonatal resuscitation (OR 1.04, 95% CI: 0.22-1.42), and Apgar score <7 (OR 0.48, 95% CI: 0.17-1.33) were not associated with oxytocin administration during labor.

CONCLUSIONS

Oxytocin administration during labor for low-risk women may lead to worse birth outcomes with an increased risk of instrumental birth and cesarean, episiotomy and the use of epidural analgesia for pain relief. Neonatal results may be also worse with an increased proportion of neonates displaying an umbilical arterial pH ≤ 7.20.

Epidural analgesia during birth and adverse neonatal outcomes: A population-based cohort study

BACKGROUND

In general, epidural analgesia is considered a safe and efficient way to relieve pain during active labour and is increasingly used in childbirth. It is well documented that epidural analgesia during birth has benefits but also adverse effects. However, evidence is limited on how epidural analgesia influences neonatal outcome in a low-risk population of birthing women.

AIM

To examine low Apgar score, foetal hypoxia and admission to the neonatal intensive care unit in neonates of low-risk women receiving epidural analgesia during birth.

METHODS

A cohort study using registry data to investigate a population of 23,272 low-risk women giving birth at a university hospital.

RESULTS

Epidural analgesia was used in 21.6% of low-risk women during birth. Low Apgar score, foetal hypoxia, and admission to the neonatal intensive care unit were found in 0.6%, 0.6%, and 10.0%, respectively in neonates of mothers receiving epidural analgesia during birth compared to 0.3%, 0.6%, and 5.6%, respectively in the non-exposed group. Epidural analgesia was associated with low Apgar score, adjusted odds ratio 1.76 (95% CI 1.07-2.90) and admission to the neonatal intensive care unit, adjusted odds ratio 1.43 (95% CI 1.26-1.62). A mediation analysis indicates the impact of epidural analgesia on adverse neonatal outcomes was mediated by obstetric complications like maternal fever, labour augmentation, and foetal malpresentation.

CONCLUSION

This study found use of epidural analgesia during birth in low-risk pregnant women was associated with infant low Apgar score and admission to the neonatal intensive care unit.

Cervical dilation at the time of epidural catheter insertion is not associated with the degree of prolongation of the first or second stages of labor, or the rate of instrumental vaginal delivery

INTRODUCTION

Epidural analgesia (EA) is an established option for efficient intrapartum analgesia. Meta-analyses have shown that EA differentially affects the first stage of labor but prolongs the second. The question of EA timing remains open. We aimed to investigate whether EA prolongs delivery in total and whether the EA administration timing vis-à-vis cervical dilation at catheter insertion is associated with a modulation of its effects on the duration of the first and second stages, as well as the rate of instrumental vaginal delivery in primiparas and multiparas.

MATERIAL AND METHODS

A retrospective electronic medical records-based study of 18 870 singleton term deliveries occurring in our institution from 2003 to 2015. Cervical dilation was determined within a half-hour of EA administration. We examined whether cervical dilation at EA administration correlated with the duration of the first and/or second stage, with the rate of prolonged second stage, and with the rate of interventional delivery. The study group was stratified to 10 subgroups defined by 1-cm intervals of cervical dilation at EA administration. Logistic regression modeling was applied to analyze the association between EA timing and rate of instrumental delivery while controlling for possible confounders.

RESULTS

In primiparas, receiving EA correlated with longer medians of active first stage (+51 minutes; P < .001) and second stage (+55 minutes; P < .001). In multiparas, median increases in active first stage (+43 minutes; P < .001) and second stage (+8 minutes; P < .001) were noted. The timing of EA, vis-à-vis cervical dilation (1-10 cm) was not associated with a substantial modulation of these effects. Logistic regression showed that cervical dilation at EA was not associated with a higher instrumental vaginal delivery rate.

CONCLUSIONS

Epidural analgesia prolonged the first and second stages of labor vs no epidural. Having EA was associated with a higher instrumental delivery rate but not with higher rates of maternal or neonatal complications, in primi- and multiparas. Importantly, the timing of EA, vis-à-vis cervical dilation, was not associated with substantial changes in the duration of labor stages or the instrumental delivery rate. Thus, EA may be offered early in the first stage of labor.

Labor progression of women attempting vaginal birth after previous cesarean delivery with or without epidural analgesia

PURPOSE

Normal labor curves have not been assessed for women undergoing a trial of labor after cesarean delivery (TOLAC). This study examined labor patterns during TOLAC in relation to epidural analgesia use.

METHODS

Retrospective cohort study of deliveries of women undergoing TOLAC at a single, academic, tertiary medical center. Length of first, second and third stages of labor was compared between 424 women undergoing TOLAC in the current labor with no previous vaginal delivery (VD) and 357 women with at least one previous VD and current TOLAC.

RESULTS

Women in the TOLAC only group had significantly longer labors compared to women in the previous VD and TOLAC group. In both groups, women who underwent epidural analgesia had longer first and second stages of labor. In the TOLAC only group, more women who had epidural analgesia tended to deliver vaginally as compared to those who did not (P = 0.09). For women who delivered vaginally, the 95th percentile for the second stage duration with epidural was 3.40 h in the TOLAC only group and 2.3 h in the previous VD and TOLAC group. The 95th percentile for the second stage duration without epidural was 1.4 h in the TOLAC only group and 0.9 h in the previous VD and TOLAC group.

CONCLUSIONS

Operative intervention (instrumental delivery/cesarean delivery (CD)) might be considered for women attempting TOLAC after a 2-h duration of second stage without epidural and 3-h duration with epidural, with an hour less for women who also had previous VD.

What women want? Results from a prospective multicenter study on women's preference about pain management during labour

OBJECTIVE

The aim of this study was to assess women preference about pain and duration of labour applying a standardized questionnaire.

STUDY DESIGN

A prospective multicentre large cohort study was carried out in two different University Hospitals. A standardized questionnaire was proposed before active labour and the day after delivery in order to investigate whether women preferred low pain intensity for a longer labour duration or greater pain intensity for a shorter labour duration. The studied population was divided and analysed in two groups according to Epidural Analgesia (EA) administration. A multivariable linear regression analysis was performed to assess which variables were able to influence the opinion about the pain perception after birth.

RESULTS

EA group showed an increased risk of episiotomy (p = 0.004), of longer duration of labour (Stage I, p < 0.001; Stage II, p = 0.002) and of oxytocin augmentation (P = 0.030). No statistical differences were found about the route of delivery between the two groups. Rates of pre-labour scores significantly differed from rates of post labour scores (p < 0.001). In the multivariable linear regression analysis, pre-labour score was directly related to post-labour score (p = 0.013). The EA was indirectly related to higher pain levels for a longer duration preference (p = 0.001), whereas oxytocic infusion in labour was directly related with preference for higher pain for a shorter duration (p = 0.011).

CONCLUSIONS

Patients' preferences about labour are focused on both pain relief and labour duration. The standardized questionnaire could be a useful tool to screen patients eligible for EA.

Perinatal outcome of vaginal delivery with epidural analgesia initiated at the early or late phase of labor period: A retrospective cohort study in the Japanese population

AIM

We compared the perinatal outcomes of vaginal delivery with epidural analgesia initiated at the early versus late phase in a Japanese population.

METHODS

Women enrolled in this retrospective cohort study received intrapartum analgesia via combined spinal epidural analgesia after labor onset between May 2010 and August 2015. We compared the perinatal outcomes between two different timings of epidural analgesia: at the early phase (≤3 cm cervical dilatation) and the late phase (≥4 cm) or at the new definition-based early phase (≤5 cm) and late phase (≥6 cm).

RESULTS

One hundred twenty-eight singleton pregnant women were eligible. In nulliparous women, there was no marked difference in perinatal outcomes between the early and late phase except for in the first-stage labor period (13.7 h vs 10.1 h, P = 0.016). In multiparous women, there was no marked difference in perinatal outcomes between the early and late phase except for a higher proportion of Apgar score ≤7 at 1 min in the early phase (20.0% vs 0.0%, P = 0.033). In nulliparous women, the first-stage labor period in the new early phase was significantly longer than in the new late phase (13.3 h vs 6.9 h, P = 0.035). Other variables for nulliparous women and all for multiparous women were not different between the new early and late phases.

CONCLUSION

Most perinatal outcomes between the early and late phases of initiated epidural analgesia were not markedly different in our Japanese population, even when using a new definition of labor phase.

Health and morbidity among Bedouin women in southern Israel: a descriptive literature review of the past two decades

In this paper we describe health and morbidity characteristics of Bedouin women in southern Israel, based on papers published over the past 20 years. This is a unique population whose customs, tradition, singular circumstances as a population "in transit", and underprivileged socio-economic status are reflected in mental illness, pregnancy course, perinatal morbidity and mortality rates, and acute and chronic disease. Recognition of these characteristics can help the medical team treat various health problems in this population as well as other populations with similar characteristics.

Differential effects of epidural analgesia on modes of delivery and perinatal outcomes between nulliparous and multiparous women: a retrospective cohort study

Background

Epidural analgesia is considered one of the most effective methods for pain relief during labor. However, it is not clear whether similar effects of epidural analgesia on the progression of labor, modes of delivery, and perinatal outcomes exist between nulliparous and multiparous women.

Methodology/Principal Findings

A retrospective cohort study was conducted to analyze all deliveries after 37 weeks of gestation, with the exclusion of pregnancies complicated by multiple gestations and fetal anomalies and deliveries without trials of labor; these criteria produced a study population of n=16,852. A multivariable logistic regression model was constructed to control for confounders. In total, 7260 of 10,175 (71.4%) nulliparous and 2987 of 6677 (44.7%) multiparous parturients were administered epidural analgesia. The independent factors for intrapartum epidural analgesia included a low prepregnancy body mass index, genetic amniocentesis, group B streptococcal colonization of the genito-rectal tract, and augmentation and induction of labor. In the nulliparous women, epidural analgesia was a significant risk factor for operative vaginal delivery (adjusted odds ratio [OR] 2.14, 95% confidence interval [CI] 1.80-2.54); however, it was a protective factor against Caesarean delivery (adjusted OR 0.62, 95% CI 0.55-0.69). Epidural analgesia remained a significant risk factor for operative vaginal delivery (adjusted OR 2.17, 95% CI 1.58-2.97) but not for Caesarean delivery (adjusted OR 1.09, 95% CI 0.77-1.55) in the multiparous women. Furthermore, the women who were administered epidural analgesia during the trials of labor had similar rates of adverse perinatal outcomes compared with the women who were not administered epidural analgesia, except that a higher rate of 1-minute Apgar scores less than 7 was noted in the nulliparous women who were administered epidural analgesia.

Conclusions/Significance

Intrapartum epidural analgesia has differential effects on the modes of delivery between nulliparous and multiparous women, and it is not associated with adverse perinatal outcomes.

Effects of maternal epidural analgesia on the neonate--a prospective cohort study

Background

Epidural analgesia is one of the most popular modes of analgesia for child birth. There are controversies regarding adverse effects and safety of epidural analgesia. This study was conducted to study the immediate effects of the maternal epidural analgesia on the neonate during early neonatal phase.

Methods

A prospective cohort study of 100 neonates born to mothers administered epidural analgesia were compared with 100 neonates born to mothers not administered epidural analgesia in terms of passage of urine, initiation of breast feeding, birth asphyxia and incidence of instrumentation.

Results

There was significant difference among the two groups in the passage of urine (P value 0.002) and incidence of instrumentation (P value 0.010) but there was no significant difference in regards to initiation of breast feeding and birth asphyxia.

Conclusions

Epidural analgesia does not have any effect on the newborns in regards to breast feeding and birth asphyxia but did have effects like delayed passage of urine and increased incidence of instrumentation.

Titrated oral misoprostol for augmenting labour to improve maternal and neonatal outcomes

BACKGROUND

Labour dystocia is associated with a number of adverse maternal and neonatal outcomes. Augmentation of labour is a commonly used intervention in cases of labour dystocia. Misoprostol is an inexpensive and stable prostaglandin E1 analogue that can be administered orally, vaginally, sublingually or rectally. Misoprostol has proven to be effective at stimulating uterine contractions although it can have serious, and even life-threatening side-effects. Titration refers to the process of adjusting the dose, frequency, or both, of a medication on the basis of frequent review to achieve optimal outcomes. Studies have reported on a range of misoprostol titration regimens used for labour induction and titrated misoprostol may potentially be effective and safe for augmentation of labour.

OBJECTIVES

To examine the effects and safety of titrated oral misoprostol compared with placebo, oxytocin, other interventions, or no active treatment, in women with labour dystocia.

SEARCH METHODS

The Trials Search Co-ordinator of the Cochrane Pregnancy and Childbirth Group searched the Cochrane Pregnancy and Childbirth Group's Trials Register; date of search: 29 May 2013. We also searched the reference lists of retrieved studies

SELECTION CRITERIA

Randomised trials (including quasi-randomised and cluster-randomised trials) comparing titrated oral misoprostol with placebo, other interventions (e.g. oxytocin, other prostaglandins), or no treatment in women requiring augmentation of labour were eligible for inclusion.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed eligibility for inclusion, carried out data extraction and assessed risk of bias in included studies. Data were entered by one author and checked for accuracy.

MAIN RESULTS

We included two randomised trials with a total of 581 women each comparing different regimens of titrated oral misoprostol with intravenous oxytocin. One study compared 20 mcg doses of misoprostol dissolved in water (repeated every hour up to four hours, after which the dose was increased to 40 mcg per hour up to a maximum total dose of 1600 mcg), while the second study gave women 75 mcg doses (repeated after four hours provided there were no adverse effects observed).Neither trial reported maternal death, severe maternal morbidity, or fetal/neonatal mortality outcomes, and only a few fetal/neonatal morbidity outcomes were considered, none of which were significantly different between groups. For several outcomes (such as maternal side-effects, instrumental birth, maternal blood transfusion for hypovolaemia and epidural analgesia), the number of events was generally too low for sufficient statistical power to be achieved. Maternal satisfaction was not reported in either trial. One trial reported a slight reduction in the median duration of labour from the start of augmentation to vaginal delivery in the oxytocin group.Neither trial reported significantly higher rates of caesarean section (CS) in the oral misoprostol group. Rates of vaginal delivery within 12 and 24 hours of commencing augmentation were not significantly different in the trial using a 20 mcg misoprostol dose. Neither trial had significantly higher rates of uterine hyperstimulation with fetal heart rate changes in the titrated oral misoprostol group. However, the rates of this outcome varied so greatly between the two studies as to suggest that other factors were at play. The only significant differences between groups related to uterine hyperstimulation (without fetal heart rate changes), and results were not consistent in the two trials. In the trial examining the higher dose of misoprostol, more women in the misoprostol group experienced hyperstimulation of labour measured over a 10-minute period compared with those receiving oxytocin (risk ratio (RR) 1.17, 95% confidence interval (CI) 1.02 to 1.35, 350 women). In the study examining the lower titrated dose of misoprostol, there was a lower incidence of tachysystole when labour was augmented with titrated oral misoprostol than with oxytocin (RR 0.39, 95% CI 0.17 to 0.91, 231 women) with no occurrences of hypertonus in either group of women.

AUTHORS' CONCLUSIONS

Important uncertainties still exist on the safety and acceptability of titrated oral misoprostol compared with intravenous oxytocin regimens in women with dystocia following spontaneous onset of labour. Although in facilities where electronic oxytocin infusion is not available, low-dose titrated misoprostol may offer a better alternative to an uncontrolled oxytocin infusion to avoid hyperstimulation. Further research is needed in both high- and low-resource settings More trials should be conducted to evaluate the effect of a standard titration oral misoprostol regimen, both following spontaneous labour and labour induction. Comparisons with other augmentation methods are also warranted, as are any effects on women's birth experiences.

Oxytocin and dystocia as risk factors for adverse birth outcomes: a cohort of low-risk nulliparous women

OBJECTIVES

augmented and not augmented women without dystocia were compared to investigate associations between oxytocin and adverse birth outcomes. Augmented women with and without dystocia were compared, to investigate associations between dystocia and adverse birth outcomes.

DESIGN

a cohort of low-risk nulliparous women originally included in a randomised controlled trial.

SETTING

the Department of Obstetrics and Gynaecology, Østfold Hospital Trust, Norway.

PARTICIPANTS

the study population consists of 747 well defined low-risk women.

MEASUREMENTS

incidence of oxytocin augmentation, and associations between dystocia and augmentation, and mode of delivery, transfer of newborns to the intensive care unit, episiotomy and postpartum haemorrhage.

FINDINGS

of all participants 327 (43.8%) were augmented with oxytocin of which 139 (42.5%) did not fulfil the criteria for dystocia. Analyses adjusted for possible confounders found that women without dystocia had an increased risk of instrumental vaginal birth (OR 3.73, CI 1.93-7.21) and episiotomy (OR 2.47, CI 1.38-4.39) if augmented with oxytocin. Augmented women had longer active phase if vaginally delivered and longer labours if delivered by caesarean section if having dystocia. Among women without dystocia, those augmented had higher body mass index, gave birth to heavier babies, had longer labours if vaginally delivered and had epidural analgesia more often compared to women not augmented.

KEY CONCLUSION

in low-risk nulliparous without dystocia, we found an association between the use of oxytocin and an increased risk of instrumental vaginal birth and episiotomy.

IMPLICATIONS FOR PRACTICE

careful attention should be paid to criteria for labour progression and guidelines for oxytocin augmentation to avoid unnecessary use.

A prospective study of effects of psychological factors and sleep on obstetric interventions, mode of birth, and neonatal outcomes among low-risk British Columbian women

Background

Obstetrical interventions, including caesarean sections, are increasing in Canada. Canadian women’s psychological states, fatigue, and sleep have not been examined prospectively for contributions to obstetric interventions and adverse neonatal outcomes.

Context and purpose of the study: The prospective study was conducted in British Columbia (BC), Canada with 650 low-risk pregnant women. Of those women, 624 were included in this study. Women were recruited through providers’ offices, media, posters, and pregnancy fairs. We examined associations between pregnant women’s fatigue, sleep deprivation, and psychological states (anxiety and childbirth fear) and women’s exposure to obstetrical interventions and adverse neonatal outcomes (preterm, admission to NICU, low APGARS, and low birth weight).

Methods

Data from our cross-sectional survey were linked, using women’s personal health numbers, to birth outcomes from the Perinatal Services BC database. After stratifying for parity, we used Pearson’s Chi-square to examine associations between psychological states, fatigue, sleep deprivation and maternal characteristics. We used hierarchical logistic regression modeling to test 9 hypotheses comparing women with high and low childbirth fear and anxiety on likelihood of having epidural anaesthetic, a caesarean section (stratified for parity), assisted vaginal delivery, and adverse neonatal outcomes and women with and without sleep deprivation and high levels of fatigue on likelihood of giving birth by caesarean section, while controlling for maternal, obstetrical (e.g., infant macrosomia), and psychological variables.

Results

Significantly higher proportions of multiparas, reporting difficult and upsetting labours and births, expectations of childbirth interventions, and health stressors, reported high levels of childbirth fear. Women who reported antenatal relationship, housing, financial, and health stressors and multiparas reporting low family incomes were significantly more likely to report high anxiety levels. The hypothesis that high childbirth fear significantly increased the risk of using epidural anaesthesia was supported.

Conclusions

Controlling for some psychological states and sleep quality while examining other contributors to outcomes decreases the likelihood of linking childbirth fear anxiety, sleep deprivation, and fatigue to increased odds of caesarean section. Ameliorating women’s childbirth fear to reduce their exposure to epidural anaesthesia can occur through developing effective interventions. These include helping multiparous women process previous experiences of difficult and upsetting labour and birth.