Length Of Second Stage Research Articles

Determination of antepartum and intrapartum risk factors associated with neonatal intensive care unit admission.

To determine antepartum and intrapartum factors that are associated with admission to neonatal intensive care unit (NICU) among infants delivered between 36.0 and 42.0 weeks at our institution. The retrospective cohort study included 73 consecutive NICU admissions and 375 consecutive non-NICU admissions. Data on demographic, antepartum, intrapartum and neonatal factors were collected. The primary endpoint defined was admission to NICU. Univariate analyses using the Student's t-test, Mann-Whitney U-test, χ2 Fisher's exact test was performed along with multivariate analysis of significant non-redundant variables. Those with a significantly higher risk of NICU admission underwent induction of labor with prostaglandin analogs (12.5% vs. 24.7%, P=0.007). Length of first stage ≥720 min (33.5% vs. 51.9%, P=0.011), length of second stage of labor ≥240 min (10.6% vs. 31.6%, P<0.001) and prolonged rupture of membranes ≥120 min (54.0% vs. 80.0%, P=0.001) were all associated with an increased chance of NICU admission. Intrapartum factors predictive of NICU admission included administration of meperidine (11.7% vs. 27.4%, P<0.001), presence of preeclampsia (5.5% vs. 0.8%, P=0.015), use of intrapartum IV antihypertensives (1.1% vs. 13.7%, P<0.001), maternal fever (5.3% vs. 31.5%, P<0.001), fetal tachycardia (1.9% vs. 12.3%, P<0.001), and presence of meconium (30% vs. 8%, P<0.001). Identification of modifiable risk factors may reduce neonatal morbidity and mortality. Results from this study can be used to develop and validate a risk model based on combined antepartum and intrapartum risk factors.

The impact of obstetric gel on the second stage of labor and perineal integrity: a randomized controlled trial

Objective: Dianatal® is a bioadhesive gliding film which reduces the opposing force to vaginal childbirth. We aimed to investigate the safety, applicability, and impact of Dianatal® obstetric gel on second stage of labor and perineal integrity.Methods: Low-risk singleton pregnancies at term were prospectively enrolled. Eligible women were randomly assigned to either labor management without using obstetric gel, or labor management using intermittent application of obstetric gel into the birth canal during vaginal examinations, starting at active phase of labor (≥4 cm dilation). The primary measured outcome was the length of second stage of labor.Results: Overall, 200 cases were analyzed. Demographic, obstetrical, and labor characteristics were similar between the groups. Neither adverse events nor maternal or neonatal side effects were observed. The mean lengths of the active and second stages of labor were comparable between the obstetric gel-treated and the control groups (157 versus 219 min and 48 versus 56 min, respectively). None of the women had grade III/IV perineal tears. Maternal and neonatal outcomes were not negatively influenced by using obstetric gel. No difference was found after sub-group analysis for spontaneous vaginal delivery.Conclusion: Dianatal® obstetric gel is safe in terms of maternal or neonatal use. Albeit a trend toward shorter labor stages using Dianatal® obstetric gel, no significant differences were noted among the groups. In order to further investigate the influence of the obstetric gel on labor stage interval, perineal integrity and maternal and neonatal outcomes, larger randomized clinical trials are needed to be carried out.

Risk factors for accidental dural puncture during epidural anesthesia for laboring women

Background and objectives: Accidental dural puncture (ADP) during epidural analgesia is a debilitating complication. Symptoms of ADP post-dural puncture headache (PDPH) are headache while rising from supine to upright position, nausea, and neck stiffness. While age, gender and needle characteristics are established risk factors for ADP, little is known about risk factors in laboring women. Methods: All cases of ADP during epidural analgesia treated with blood-patching during a 3-years period were retrospectively reviewed. Each case was matched to two controls according to delivery period. Results: Forty-nine cases of blood patches after ADP out 17 977 epidural anesthesia procedures were identified (0.27%). No differences were found between cases and controls with regards to body mass index, labor stage at time of epidural, length of second stage, location of epidural along the lumbar vertebrae, anesthesiologist’s experience or time when epidural was done. In cases of ADP, significantly lower doses of local anesthetics were injected (10.9 versus 13.5 cc, p < 0.001); anesthesiologists reported significantly more trials of epidurals (70 versus 2.8% more than one trial, p < 0.001), more patient movement during the procedure (13 versus 0%, p < 0.001), more intra-procedure suspicion of ADP (69 versus 0%, p < 0.001) and more cases where CSF/blood was drawn with the syringe (57 versus 2.4%, p < 0.001). Conclusion: ADP during labor is a rare but debilitating complication. Risk factors for this iatrogenic complication include patient movement and repeated epidural trials. Intra-procedure identification of ADP is common, allowing early intervention with blood patching where indicated.

Length of second stage of labor and preterm birth in a subsequent pregnancy

During the second stage of labor, it is plausible that the pressure of the fetal head against a completely dilated cervix may lead to changes in the cervical integrity and cervical strength lending it susceptible to premature dilation in a subsequent pregnancy. Therefore, a prolonged second stage of labor has been hypothesized to be a risk factor for cervical insufficiency and spontaneous preterm birth (sPTB). We sought to evaluate the effect that the length of second stage of labor in one pregnancy has on the risk of sPTB in a subsequent pregnancy. This was a planned secondary analysis of a large retrospective cohort study of women with 2 consecutive deliveries at our institution from 2005 through 2010. Women with a term pregnancy that reached the second stage were included; women with a prior sPTB were excluded. The primary outcome was sPTB <37 weeks. A prolonged second stage was defined as ≥3 hours. Fisher exact tests were used to compare categorical data. Linear and logistic regression was used to calculate odds. In all, 757 women were included. The overall length of the second stage ranged from 0-7.3 hours. The sPTB rate in a subsequent pregnancy was 8.7%. There was no association between length of second stage (hours) as a continuous variable and sPTB after adjusting for confounders (adjusted odds ratio, 0.83; [95% CI 0.58-1.20]). A prolonged second stage ≥3 hours occurred in 48 (6.3%) women. Women with a second stage ≥3 hours were older, less likely to be African American, and were less likely to be overweight or obese as compared to women with a second stage <3 hours. The women with second stage ≥3 hours were more likely to be nulliparous and have a larger neonate. The sPTB risk was not different between a second stage ≥3 hours (10.4%) and <3 hours (7.9%), P = .5. The sPTB risk was, however, modified by mode of delivery in the second stage. There was no difference in sPTB rate among women with a vaginal delivery when comparing those with and without a prolonged second stage (7.4 vs 7.8%, P = .9). There also was no difference among women with a cesarean when comparing those with and without a prolonged second stage (11.8 vs 14.3%, P = .8). While not statistically significant, the absolute risk of a subsequent sPTB after a cesarean delivery with a second stage ≥3 hours is twice as high as the risk of a sPTB after a vaginal delivery with a second stage ≥3 hours (adjusted odds ratio, 2.08; [0.32-13.78]). A prolonged second stage of labor alone does not increase the risk of sPTB in a subsequent pregnancy. Cesarean delivery after a prolonged second stage of labor may confer a possible increased risk. It is important to continue to evaluate potential risk factors for sPTB. If these risk factors are confirmed in future studies, it will aid in the counseling of women and may open the door for therapeutic strategies to be studied among these newly identified at-risk women.

Prolonged second stage of labor is associated with low Apgar score

There is no consensus on the effects of a prolonged second stage of labor on neonatal outcomes. In this large Swedish population-based cohort study, our objective was to investigate prolonged second stage and risk of low Apgar score at 5 min. All nulliparous women (n = 32,796) delivering a live born singleton infant in cephalic presentation at ≥37 completed weeks after spontaneous onset of labor between 2008 and 2012 in the counties of Stockholm and Gotland were included. Data were obtained from computerized records. Exposure was time from fully retracted cervix until delivery. Logistic regression analyses were used to estimate crude and adjusted odds ratios (ORs) with 95% confidence intervals (CIs). Adjustments were made for maternal age, height, BMI, smoking, sex, gestational age, sex-specific birth weight for gestational age and head circumference. Epidural analgesia was included in a second model. The primary outcome measure was Apgar score at 5 min <7 and <4. We found that the overall rates of 5 min Apgar score <7 and <4 were 7.0 and 1.3 per 1000 births, respectively. Compared to women with <1 h from retracted cervix to birth, adjusted ORs of Apgar score <7 at 5 min generally increased with length of second stage of labor: 1 to <2 h: OR 1.78 (95% CI 1.19-2.66); 2 to <3 h: OR 1.66 (1.05-2.62); 3 to <4 h: OR 2.08 (1.29-3.35); and ≥4 h: OR 2.71 (1.67-4.40). We conclude that prolonged second stage of labor is associated with an increased risk of low 5 min Apgar score.

Second Stage of Labor and Epidural Use

OBJECTIVE:To examine the length of second stage of labor with and without an epidural during labor.METHODS:This was a retrospective cohort study of 42,268 women who delivered vaginally with normal neonatal outcomes. Median lengths and 95th percentiles of second stage of labor were compared by epidur

19: Optimizing second stage outcomes: a randomized controled trial assessing the ability of precise maternal feedback to reduce adverse perinatal outcomes

19 Optimizing second stage outcomes: a randomized controled trial assessing the ability of precise maternal feedback to reduce adverse perinatal outcomes Merlin Fausett, P. Barrilleaux, Jonnie Buford Women’s and Childrens Hospital, OB/GYN, Lafayette, LA, Community Medical Center, OB/GYN, Missoula, MT OBJECTIVE: Regional anesthesia reduces biofeedback impeding pushing efficacy during second stage labor. Long second stage is associated with adverse outcomes. We assessed the clinical impact of providing laboring women real-time audiovisual feedback regarding fetal descent during second stage. STUDY DESIGN: Abiofeedback device detecting fetal decentwas attached to 69 primigravidas receiving epidural anesthesia. Fetal decent was measured & conveyed at sub-second and sub-millimeter intervals. After attachment of the feedback device, women were randomized 2:1 to Feedback (Study) and No Feedback (Control) groups. The 45 women in the Study groupwere provided audiovisual feedback. Second stage management was otherwise routine in both groups. The primary outcome of interest was length of second stage (LSS). Secondarily, we assessed individual adverse outcomes (AO) rates for operative vaginal delivery (OVD), cesarean delivery (CS), 3rd/4th degree laceration (LAC), intra-amniotic infection (IAI), perineal edema (E) and NICU admissions. Length of second stage regression models controlled for initial head station (HS) and birth weight (BW). RESULTS: For women delivering vaginally, the median pushing time was 58 vs. 77 minutes for Study and Control groups respectively. The lower 3 quartiles of the Study group had a 23 minute (26%) reduction in LSS (p1⁄40.016), see Figure 1. The AO rates of OVD, LAC, IAI, and E were all lower in the Study group (all p values < 0.02). The CS rate was not different but the composite AO rate was 73% lower in the Study group (p 1⁄4 0.011)-Table 1. Women with any AO, had a mean 2 hour increased hospital length of stay, p<0.01. CONCLUSION: A system providing precise measurement of fetal decent and maternal feedback during second stage labor substantially shortens second stage. In nulliparous women with epidural anesthesia, this feedback system decreases key individual and composite adverse maternal outcomes and decreases NICU admissions.

504: Length of second stage of labor and risk of preterm birth in a subsequent pregnancy

A prolonged second stage (SS) of labor may alter the cervical stroma and integrity of the cervix, thereby increasing the risk for spontaneous PTB (sPTB) in a subsequent pregnancy. We aimed to evaluate the impact that length of SS has on subsequent sPTB risk. We performed a retrospective cohort study of women with 2 consecutive deliveries from 2005-2010 at one institution. Women were included if the first of the 2 deliveries was a term delivery that reached the SS and if they had a subsequent delivery ≥16 weeks. Women with a prior PTB were excluded. The primary outcome was sPTB (<37wks) in a subsequent pregnancy. Categorical variables were compared with χ2 analyses. Logistic regression was used to calculate odds. 757 women met inclusion criteria. The subsequent sPTB rate for this term cohort was 8.7%. The overall SS varied in length from 0-7.3hrs (figure). There was no significant association between overall length of SS and subsequent sPTB risk (OR 0.93 [0.73-1.12], p=0.6), regardless of mode of delivery. We then evaluated women who had a SS ≥2 hours (n=99, 13.1%). Regardless of mode of delivery, the risk of subsequent sPTB was not statistically different between those with a SS ≥2 hours compared to <2 hours (OR 0.85 [0.38-1.93], p=0.7). However, when focusing only on women with SS ≥2 hours and comparing mode of delivery, the risk of subsequent sPTB after a cesarean with a SS ≥2 hours is significantly higher than the risk of sPTB after a vaginal delivery with SS ≥2 hours (17.9% vs. 2.8%, p=0.009). In other words, the odds of having a sPTB after a cesarean and SS ≥2 hours was 7.5 times higher than the odds of having a sPTB after a vaginal delivery and SS ≥2 hours (OR 7.5 [1.4-41.3], p=0.02). The overall length of SS does not impact the risk of sPTB. However, women with a cesarean after a SS ≥2 hours have a significantly higher risk of sPTB compared to women with a vaginal delivery after a SS ≥2 hours. Future studies should investigate the etiology of this increased risk.

Is there an association between sonographically determined occipito-transverse position in the second stage of labor and operative delivery?

To evaluate if ultrasound-determined occipito-transverse position early in the second stage of labor is associated with operative delivery. Retrospective review of two prospective cohort studies. An Australian tertiary referral hospital. Women with term, cephalic singleton pregnancies. Retrospective analysis of data from two prospective studies. Logistic regression was undertaken to assess the independent contribution of the occipito-transverse position to operative delivery. Operative delivery (cesarean section, forceps or vacuum extraction). Among 422 women included, the occipito-transverse position was present in 80, occipito-anterior in 303 and the occipito-posterior in 39. Compared with occipito-anterior, the adjusted odds ratio for operative delivery was 2.1 (95% confidence interval 1.2-3.8, p = 0.02) for the occipito-transverse position, and 7.4 (95% confidence interval 3.2-17) for the occipito-posterior position. Factors that independently predicted operative delivery were nulliparity, abnormal second stage cardiotocography, maternal place of birth and epidural analgesia. The length of second stage of labor was longer for the occipito-transverse group than for the occipito-anterior group (median 2 h 7 min vs. 1 h 36 min, p = 0.003). The occipito-transverse position early in the second stage of labor was associated with an increased operative delivery rate.

Second Stage of Labor and Epidural Use

To examine the length of second stage of labor with and without an epidural during labor. This was a retrospective cohort study of 42,268 women who delivered vaginally with normal neonatal outcomes. Median lengths and 95th percentiles of second stage of labor were compared by epidural use with stratification by parity. Statistical comparisons were performed using the Kruskal-Wallis test and Kaplan-Meier survival analysis. Compared with women without epidural use, the 95th percentile length of second stage for nulliparous women was 197 minutes without epidural and 336 minutes with epidural (P<.001), a difference of 2 hours and 19 minutes. For multiparous women, the 95th percentile length of second stage was 81 minutes without epidural and 255 minutes with epidural (P<.001), a difference of 2 hours and 54 minutes. Although recommendations for intervention during the second stage of labor have been made based on a 1-hour difference in the setting of epidural use, it appears that the 95th percentile duration is actually more than 2 hours longer with epidural during labor for both nulliparous and multiparous women.

Levator hiatus dimensions in late pregnancy and the process of labor: a 3- and 4-dimensional transperineal ultrasound study

The objectives of the investigation were to study the association between levator hiatus dimensions in late pregnancy and both the length of second stage of labor and also the delivery mode in women delivering their first child. In this cohort study, 231 nulliparous women were examined with 3- and 4-dimensional transperineal ultrasonography at 37 weeks of gestation. The anteroposterior, transverse diameter, and the area of levator hiatus were measured at rest, during levator ani muscle contraction, and during Valsalva maneuver. The second stage of labor was divided into passive and active second stage and delivery modes into normal vaginal or instrumental deliveries. Spearman correlation coefficient, independent-sample t test, and standard logistic regression were used for analysis. Larger levator hiatus dimensions at rest and during contraction at 37 weeks of gestation correlated with a shorter duration of the active second stage in women with normal vaginal delivery (Spearman correlation coefficient, -0.13 to -0.35, P ≤ .08). Women having normal vaginal deliveries had significantly larger transverse diameter at rest, during contraction, and during Valsalva maneuver compared with women having instrumental deliveries (mean difference, 0.29; 95% confidence interval (CI), 0.16-0.41; mean difference, 0.33; 95% CI, 0.21-0.44 and mean difference, 0.24; 95% CI, 0.06-0.42; P < .05). The same was true for the levator hiatus area at rest and during contraction (mean difference, 1.22; 95% CI, 0.37-2.07 and mean difference, 0.84; 95% CI, 0.22-1.46; P < .01). These estimates were unchanged by adjustments in the logistic regression analysis. Larger levator hiatus dimensions in late pregnancy had a significant association with a shorter active second stage of labor and normal vaginal delivery.

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A novel two-staged photonic transistor with high operating speed, low switching power and high switching gain was recently proposed. Based on the manipulation of optical interference in an active directional coupler by optically controlled absorption and gain, two complementary device types were conceptually evaluated through the use of time domain technique showing ~105 times higher figure of merit compared to conventional approaches. With the joint usage of both device types, the photonic transistor could function as wavelength converter, pulse regenerator and logical operator. In this work, we identify the operational regimes of the photonic transistor that helps in reducing the footprint and operating intensities to achieve a switching gain of at least ~ 2 (or 3 dB). A recently proposed theoretical framework that calculates the spatial profiles of optical fields and complex permittivities seen by them in photonic structures with multiple active and passive sections is utilized for the purposes. We show that the operational intensity and wavelengths of interacting fields in the photonic transistor must be such that α0L1 > = 26 and g0L2 > = 3.2 to achieve a switching gain > = 2, where α0 = absorption coefficient of the short wavelength, g0 = pumped medium gain coefficient seen by long wavelength beams, L1 = length of first stage and L2 = length of second stage.

Relationship of the Length of the First Stage of Labor to the Length of the Second Stage

To evaluate the relationship between the lengths of the first and second stages of labor. In this observational study of women delivering at our hospital, the onset of the first stage of labor was defined as admission at 3-cm to 4-cm dilatation in the presence of uterine contractions with or without rupture of membranes. This study was limited to nulliparous women with a singleton, cephalic live birth at 37 0/7 weeks of gestation or more. Women presenting with more advanced cervical dilatation (greater than 4 cm), prior cesarean delivery, diabetes, hypertension, and placental accidents were excluded. Each woman was analyzed based on her specific lengths of first and second stages of labor, that is, paired observations for each woman. Between January 1, 2001, and June 30, 2012, a total of 172,522 women were delivered and 12,523 (7.3%) met the inclusion criteria. The 95 percentile was 15.6 and 2.9 hours for the first and second stages, respectively. Women with first stages greater than the 95 percentile had a 16.3% rate of a second-stage length greater than the 95 percentile compared with 4.5% (P<.001) in women with first stages less than the 95 percentile. This relationship persisted when analyzed for variables influencing labor to include neonate birth weight, epidural analgesia, or maternal size. Overall, the length of the second stage significantly increased concomitantly with increasing length of the first stage (P<.001). II.

Current Resources for Evidence‐Based Practice January/February 2013

Current Resources for Evidence‐Based Practice January/February 2013

342: The second stage of labor and persistent occiput posterior position: patience or intervention?

Persistent occiput posterior (OP) position is associated with longer labor and increased risk of maternal morbidity. However, little information exists regarding the “normal” labor curve of women whose fetus presents in OP position in the second stage. We aimed to examine the length of second stage in the setting of persistent OP position.

Application of Second-Stage Passive Descent in Morbidly Obese Women

To estimate whether passive descent in the second stage of labor in morbidly obese parturients is associated with reduced active pushing times and improved labor outcomes compared with immediate pushing. This was a retrospective cohort study of all consecutive women with a body mass index (BMI) of 40 or greater admitted for term labor that reached the second stage of labor from 2004 to 2008 at a single institution. Detailed information was collected for maternal demographics, labor progress, and neonatal outcomes. Length of active pushing, length of total second stage, and maternal and neonatal outcomes were compared between women selected to passive descent for at least 30 minutes and those who pushed immediately. A total of 558 women with a BMI of 40 or greater were identified; of these, 97 underwent passive descent and 461 pushed immediately. Morbidly obese women selected for passive descent were just as likely to actively push for at least 60 minutes compared with those who pushed immediately (16.5% compared with 7.2%, adjusted odds ratio [OR] 1.51, 95% confidence interval [CI] 0.74-3.12). They were also significantly more likely to push for more than 30 minutes (37.1% compared with 13.9%, adjusted OR 2.03, 95% CI 1.17-3.54). Their overall time (minutes) spent pushing was significantly longer (median 19, interquartile range 7-39 compared with median 7, interquartile range 3-17, P<.001) as was their overall length of second stage (median 81, interquartile range 57-127 compared with median 15, interquartile range 8-27, P<.001). They had similar rates of operative delivery and maternal febrile morbidity. Passive descent of morbidly obese parturients was associated with a greater amount of time actively pushing with similar rates of operative delivery and maternal febrile morbidity.

Pelvic Floor Structure and Function in Women with Vesicovaginal Fistula

Vesicovaginal fistula is a catastrophic event, especially in areas with poor peripartum care, where most occur. It is usually due to severely obstructed and protracted labor. We assumed that such patients would show evidence of abnormal levator function, eg due to denervation. In an external audit at Hamlin Fistula Hospital in Addis Ababa, Ethiopia, 95 women were seen for clinical examination and 4-dimensional translabial ultrasound. Patients were examined supine and after voiding. Volume data sets were obtained upon coughing, Valsalva maneuver and pelvic floor muscle contraction. Women were seen before (22) or after (73) vesicovaginal fistula repair. Mean age was 29.5 years (range 16 to 65) and mean parity was 2.7 (range 1 to 11). Only 2 patients had a significant cystocele (stage 2), 3 had stage 2 uterine prolapse and 13 had a stage 2 rectocele. Levator biometry was done in 92 of 95 women, which showed no evidence of muscle atrophy. Mean hiatal area on Valsalva was 18.8 cm(2) (range 7.7 to 45.9) and only 6 of the 92 women (7%) fulfilled the criteria for ballooning (hiatal distention 25 cm(2) or greater). Levator avulsion was diagnosed in 27 cases (28%), of which 11 were bilateral. Reflex contraction of the levator ani was observed upon coughing in all except 2 patients. Levator contraction upon request could be performed by all except 6 women. Abnormal levator function and anatomy in patients with vesicovaginal fistula is not uncommon but no more than in unselected urogynecologic patients in the developed world. There was no evidence of permanent denervation of the levator ani.

Second stage caesarean section – the importance of regular audit

Caesarean section in the second stage of labour is well documented to carry increased risk of morbidity.1 Complications include increased blood loss and surgical trauma.2 As such, it is important...

The impact of length of second stage of labor on shoulder dystocia outcomes: a retrospective cohort study

To compare obstetrical and neonatal outcomes of vaginal deliveries complicated by shoulder dystocia, according to the length of second stage of labor. We conducted a retrospective cohort study of 177 shoulder dystocia cases that were divided into three categories according to second stage duration (1-20, 21-59, 60-180 min, respectively). The three categories were compared in terms of obstetric characteristics and neonatal outcomes. Statistical analysis utilized the χ2-test and analysis of variance where appropriate. The odds ratios of brachial plexus injury and having a 5-min APGAR score <7 across the second stage duration categories were calculated using logistic regression models that adjusted for potential confounders. The incidence of brachial plexus injury was 5.4% (1st category), 4.4% (2nd category) and 26.9% (3rd category); P<0.01. The higher incidence of brachial plexus injury in the group where second stage lasted >1 h was confirmed by logistic regression, with and without adjusting for confounders. The incidence of brachial plexus injury increases with the length of second stage, even after controlling for confounders.

Epidural versus non-epidural or no analgesia in labour

Epidural analgesia is a central nerve block technique achieved by injection of a local anaesthetic close to the nerves that transmit pain and is widely used as a form of pain relief in labour. However, there are concerns regarding unintended adverse effects on the mother and infant. To assess the effects of all modalities of epidural analgesia (including combined-spinal-epidural) on the mother and the baby, when compared with non-epidural or no pain relief during labour. We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (31 March 2011). Randomised controlled trials comparing all modalities of epidural with any form of pain relief not involving regional blockade, or no pain relief in labour. Two of the review authors independently assessed trials for eligibility, methodological quality and extracted all data. We entered data into RevMan and double checked it for accuracy. Primary analysis was by intention to treat; we conducted subgroup and sensitivity analyses where substantial heterogeneity was evident. We included 38 studies involving 9658 women; all but five studies compared epidural analgesia with opiates. Epidural analgesia was found to offer better pain relief (mean difference (MD) -3.36, 95% confidence interval (CI) -5.41 to -1.31, three trials, 1166 women); a reduction in the need for additional pain relief (risk ratio (RR) 0.05, 95% CI 0.02 to 0.17, 15 trials, 6019 women); a reduced risk of acidosis (RR 0.80, 95% CI 0.68 to 0.94, seven trials, 3643 women); and a reduced risk of naloxone administration (RR 0.15, 95% CI 0.10 to 0.23, 10 trials, 2645 women). However, epidural analgesia was associated with an increased risk of assisted vaginal birth (RR 1.42, 95% CI 1.28 to 1.57, 23 trials, 7935 women), maternal hypotension (RR 18.23, 95% CI 5.09 to 65.35, eight trials, 2789 women), motor-blockade (RR 31.67, 95% CI 4.33 to 231.51, three trials, 322 women), maternal fever (RR 3.34, 95% CI 2.63 to 4.23, six trials, 2741 women), urinary retention (RR 17.05, 95% CI 4.82 to 60.39, three trials, 283 women), longer second stage of labour (MD 13.66 minutes, 95% CI 6.67 to 20.66, 13 trials, 4233 women), oxytocin administration (RR 1.19, 95% CI 1.03 to 1.39, 13 trials, 5815 women) and an increased risk of caesarean section for fetal distress (RR 1.43, 95% CI 1.03 to 1.97, 11 trials, 4816 women). There was no evidence of a significant difference in the risk of caesarean section overall (RR 1.10, 95% CI 0.97 to 1.25, 27 trials, 8417 women), long-term backache (RR 0.96, 95% CI 0.86 to 1.07, three trials, 1806 women), Apgar score less than seven at five minutes (RR 0.80, 95% CI 0.54 to 1.20, 18 trials, 6898 women), and maternal satisfaction with pain relief (RR 1.31, 95% CI 0.84 to 2.05, seven trials, 2929 women). We found substantial heterogeneity for the following outcomes: pain relief; maternal satisfaction; need for additional means of pain relief; length of second stage of labour; and oxytocin augmentation. This could not be explained by subgroup or sensitivity analyses, where data allowed analysis. No studies reported on rare but potentially serious adverse effects of epidural analgesia. Epidural analgesia appears to be effective in reducing pain during labour. However, women who use this form of pain relief are at increased risk of having an instrumental delivery. Epidural analgesia had no statistically significant impact on the risk of caesarean section, maternal satisfaction with pain relief and long-term backache and did not appear to have an immediate effect on neonatal status as determined by Apgar scores. Further research may be helpful to evaluate rare but potentially severe adverse effects of epidural analgesia on women in labour and long-term neonatal outcomes.