Labor course and delivery in epidural analgesia: a case-control study.

BACKGROUND: We aimed to establish if epidural analgesia is associated with a higher incidence of operative vaginal delivery, longer duration of labor and more frequent use of oxytocin than labor without analgesia. METHODS: We analyzed a cohort of 207 women with no risk factors who delivered with epidural analgesia in the labor unit of Spedali Civili, Brescia, Italy, during 2001. Length of the first and second stage of labor, mode of delivery, neonatal cord blood pH, neonatal Apgar score and neonatal outcomes were evaluated. RESULTS: Epidural analgesia was performed on request in 6%: in this group (group A) there were 141 (68%) nulliparae and 66 (32%) pluriparae; mean ( +/- standard deviation) gestational age at delivery was 39.4 +/- 1.3 weeks (range: 34.1-41.5 weeks). In this group, 184 (89%) had vaginal delivery and 23 (11%) delivered by Cesarean section. Among controls (group B), 368 (89%) had a vaginal delivery and 46 (11%) delivered by Cesarean section; vacuum extraction was used in 18 deliveries (9%) in group A and in 13 deliveries (3%) in group B. The duration of the second stage of spontaneous labor in the nulliparae of group A was significantly longer than in group B. No statistically significant differences were found between mean umbilical artery pH values of groups A and B. CONCLUSION: Our results confirm that epidural analgesia does not affect the rate of Cesarean delivery, while increasing the use of oxytocin augmentation, the duration of the second stage of labor and the rate of instrumental vaginal delivery.     

Opioid spinal anesthesia at the end of labor for potentially difficult deliveries

We report two cases of difficult delivery, one vaginal breech presentation and one vaginal twin delivery in agitated parturients who were not given epidura analgesia. Maternal agitation was caused by pain and led to the risk of difficult fetal extraction. Epidural analgesia is not useful during the second stage of labor because of delayed onset of action of the administered drugs. Spinal injection of 10 microg of sufentanil was followed by rapid analgesia, maternal sedation and atraumatic deliveries. The usefulness of this technique is discussed for analgesia during the second stage of labor when epidural analgesia has not been performed.     

Does epidural anesthesia affect the course of labor and delivery?

The progress of labor ideally leads to a normal, spontaneous, vaginal delivery. Many factors--maternal, fetal, obstetrical and anesthetic--may collectively contribute to delaying or precluding an ideal outcome. Adverse outcomes of labor and delivery must be clearly defined in terms of maternal, fetal, or neonatal morbidity or mortality, and should be distinguished from abnormal data (such as fetal heart rate, duration of labor, and incidence of low forceps deliveries) that are only indirectly related to outcome. Epidural anesthesia is not a singular phenomenon. Variations and subtle nuances in the administration of epidural anesthesia create a vast array of potential anesthetic regimens. To discover the anesthetic methods that provide excellent analgesia with no adverse effects on the course of labor is an ideal goal that has not yet been achieved. To approach this goal, the answers to several questions are needed. Are study patient groups adequately matched for risk factors? Are obstetrical practices well-defined with respect to elective versus indicated use of instrumental or cesarean delivery methods? Do the risks of instrumental delivery outweigh the benefit of perineal analgesia associated with epidural anesthesia? Is it possible to provide optimal analgesia throughout stage two labor without tending to increase the risk of instrumental delivery? Can delayed pushing during stage two labor increase the probability of spontaneous vaginal delivery with continuous epidural anesthesia? Well-controlled clinical trials and refinements in both anesthetic and obstetric techniques are necessary to resolve such issues so that every parturient (and fetus) may undergo a safe and painless delivery.     

Effect of epidural analgesia on the primary cesarean section and forceps delivery rates

OBJECTIVE: To determine the impact of introducing epidural analgesia for labor pain relief on the primary cesarean and forceps delivery rates. STUDY DESIGN: The control group consisted of 1,720 women who delivered on a charity hospital service between September 1, 1992, and August 31, 1993; epidural analgesia was not available for this cohort of patients. The study group consisted of 1,442 patients who delivered on the same service between September 1, 1993, and August 31, 1994; elective epidural analgesia for labor pain relief was available for this cohort of patients. A computerized obstetric database was analyzed to compare the two groups regarding demographics, parity, pregnancy complications, labor characteristics, type of delivery, low birth weight incidence and five-minute Apgar scores. RESULTS: The two groups were similar with respect to demographics and pregnancy complications. No control group patient received epidural analgesia for labor pain relief; 734 of 1,285 (57%) laboring patients in the study group elected epidural analgesia for pain relief. The primary cesarean delivery rate for the control group was 9.6% and for the study group 11.0% (not statistically significant). The control group had 34 (2.0%) forceps deliveries and the study group, 88 (6.1%), for a statistically significant difference. There were significantly more vaginal births after cesarean in the study group (42 vs. 26). CONCLUSION: Epidural analgesia was not associated with an increase in the primary cesarean delivery rate but was associated with an increase in the operative vaginal delivery rate.     

Epidural analgesia in association with duration of labor and mode of delivery: a quantitative review

OBJECTIVE: This study was undertaken to quantitatively summarize previous literature on the effects of epidural analgesia in labor on the duration of labor and mode of delivery. STUDY DESIGN: Original studies published in English from 1965 through December 1997 were reviewed and assigned a quality score independently by 2 of the authors. Studies that met the minimal requirements were evaluated further. Data syntheses were performed separately according to study design and outcome measurements, including cesarean delivery, instrumental delivery, oxytocin augmentation, and durations of the first and second stages of labor. RESULTS: Seven randomized clinical trials and 5 observational studies met the minimal requirements. Among them 4 studies of each sort were included in the data synthesis. Both types of studies showed that epidural analgesia increased risk of oxytocin augmentation 2-fold. Clinical trials suggested that epidural analgesia did not increase the risk of cesarean delivery either overall or for dystocia, nor did it significantly increase the risk of instrumental vaginal delivery; however, observational studies reported a more than 4-fold increased risk of cesarean and instrumental deliveries. Although most studies showed a longer labor among women with epidural analgesia than without it, especially during the second stage, most of the studies used inappropriate statistical analysis. CONCLUSION: Epidural analgesia with low-dose bupivacaine may increase the risk of oxytocin augmentation but not that of cesarean delivery.     

Risk factors for arrest of descent during the second stage of labor.

OBJECTIVE: To define obstetrical risk factors for arrest of descent during the second stage of labor and to determine perinatal outcome. STUDY DESIGN: All singleton, vertex, term deliveries with an unscarred uterus, between the years 1988 and 1999 were included. Univariable and multivariable analysis were performed to investigate independent risk factors associated with arrest of descent during the second stage of labor and the perinatal outcome. RESULTS: The study included 93266 deliveries, of these 1545 (1.7%) were complicated with arrest of descent during the second stage of labor. Using a multivariable analysis, the following obstetric risk factors were found to be significantly associated with arrest of descent: nulliparity (OR=7.8, 95% CI=6.9-8.7; P<0.001), birth weight >4 kg (OR=2.3, 95% CI=1.9-2.8; P<0.001), epidural analgesia (OR=1.8, 95% CI=1.6-2.0; P<0.001), hydramnios (OR=1.6, 95% CI=1.3-2.0; P<0.001), hypertensive disorders (OR=1.5, 95% CI=1.3-1.8; P<0.001), gestational diabetes A1 and A2 (OR=1.5, 95% CI=1.2-1.8; P<0.001), male gender (OR=1.4, 95% CI=1.2-1.5; P<0.001), premature rupture of membranes (PROM, OR=1.3, 95% CI=1.04-1.6; P=0.021), and induction of labor (OR=1.2, 95% CI=1.02-1.4; P=0.030). Deliveries complicated by arrest of descent resulted in cesarean section in 20.6%, vacuum extraction in 74.0%, and forceps delivery in 5.4%. Newborns delivered after arrest of descent during the second stage of labor had significantly higher rates of low Apgar scores (<7) at 1 and 5 min, as compared to the controls (12.7 vs. 2.1%, P<0.001; and 0.9 vs. 0.2%, P<0.001, respectively). Nevertheless, no significant differences were noted between the groups regarding perinatal mortality (0.38 vs. 0.44%; P=0.759). CONCLUSIONS: Major risk factors for arrest of descent during the second stage of labor were nulliparity, fetal macrosomia, epidural analgesia, hydramnios, hypertensive disorders and gestational diabetes mellitus. These risk factors should be carefully evaluated during pregnancy in order to actively manage high-risk pregnancies.     

Effect of epidural analgesia on operative vaginal birth rate

The aim of the study was to investigate if epidural analgesia may affect the operative vaginal birth rate. An observational study was carried out on 1,158 in low-risk patients who delivered vaginally; 46.9% of these patients underwent epidural analgesia using different doses and drugs. Overall, epidural analgesia enhanced the probability of vacuum delivery (OR 2.70 95% CI 1.88-3.89, p < 0.001). Vacuum application was increased about seven times by administration of fentanyl alone at the first dose, while it was reduced if ropivacaine was added to fentanyl. In patients undergoing epidural analgesia, increasing the amount of ropivacaine at the first dose reduced the probability of vacuum delivery (OR 0.82; 95% CI 0.67-1.00, p = 0.05). Moreover, increasing the number of top-ups reduced the probability of vacuum delivery (OR 0.49 95% CI 0.27-0.93, p = 0.029) and the time of the second stage of labor. On the other hand, increasing time from the first dose of epidural to the last top-up increased the risk of operative vaginal delivery (OR 1.33 95% CI 1.03-1.72, p = 0.031) and the time of the second stage of labor. Epidural analgesia seems to favor spontaneous delivery when it is properly carried on.     

Epidural analgesia and third- or fourth-degree lacerations in nulliparas.

OBJECTIVE: To determine if epidural analgesia is associated with differences in rates of severe perineal trauma during vaginal deliveries. METHODS: We studied 1942 consecutive, low-risk, term, vaginal deliveries in nulliparas, including spontaneous and induced labors, at a single institution from December 1994 to August 1995. The rate of third- and fourth-degree lacerations was compared for women who had and did not have epidural analgesia for labor-pain relief. Statistical significance was determined using chi2. Logistic regression analyses were used to evaluate associations while controlling for possible confounding variables. RESULTS: Overall rates of third- and fourth-degree lacerations were 10.8% (n = 210) and 3.4% (n = 63), respectively. Epidural analgesia was given to 1376 (70.9%) women. Among women who had epidurals, 16.1% (221 of 1376) had severe perineal lacerations compared with 9.7% (n = 55) of the 566 women who did not have epidurals (P < .001; odds ratio [OR] 1.8, 95% confidence interval [CI] 1.3, 2.4). When controlling for birth weight, use of oxytocin, and maternal age in logistic regression analysis, epidural remained a significant predictor of severe perineal injury (OR 1.4, 95% CI 1.0, 2.0). Epidural use is consistently associated with increased operative vaginal deliveries and consequent episiotomies, so we constructed a logistic regression model to evaluate whether the higher rates of those procedures were responsible for the effect of epidurals on severe perineal traumas. With operative vaginal delivery and episiotomy in the model, epidural was no longer an independent predictor of perineal injury (OR 0.9, 95% CI 0.6, 1.3). CONCLUSION: Epidural analgesia is associated with an increase in the rate of severe perineal trauma because of the more frequent use of operative vaginal delivery and episiotomy.     

Influence of persistent occiput posterior position on delivery outcome.

OBJECTIVE: To evaluate the influence of intrapartum persistent occiput posterior position of the fetal head on delivery outcome and anal sphincter injury, with reference to the association with epidural analgesia. METHODS: We conducted a prospective observational study of 246 women with persistent occiput posterior position in labor during a 2-year period, compared with 13,543 contemporaneous vaginal deliveries with occiput anterior position. RESULTS: The incidence of persistent occiput posterior position was significantly greater among primiparas (2.4%) than multiparas (1.3%; P <.001; 95% confidence interval 1.4, 2.4) and was associated with significantly higher incidences of prolonged pregnancy, induction of labor, oxytocin augmentation of labor, epidural use, and prolonged labor. Only 29% of primiparas and 55% of multiparas with persistent occiput posterior position achieved spontaneous vaginal delivery, and the malposition was associated with 12% of all cesarean deliveries performed because of dystocia. Persistent occiput posterior position was also associated with a sevenfold higher incidence of anal sphincter disruption. Despite a high overall incidence of use of epidural analgesia (47% versus 3%), the institutional incidence of persistent occiput posterior position was lower than that reported 25 years ago. CONCLUSION: Persistent occiput posterior position contributed disproportionately to cesarean and instrumental delivery, with fewer than half of the occiput posterior labors ending in spontaneous delivery and the position accounting for 12% of all cesarean deliveries for dystocia. Persistent occiput posterior position leads to a sevenfold increase in the incidence of anal sphincter injury. Use of epidural analgesia was not related to the malposition.     

The significance of peripartum fever in women undergoing vaginal deliveries

We investigated whether patients undergoing vaginal delivery who developed peripartum fever (PPF) had increased rates of other gestational complications. A retrospective study was undertaken comparing pregnancy complications of patients who developed PPF with those who did not. A multivariable logistic regression model was constructed to control for confounders. To avoid ascertainment bias, the year of birth was included in the model. Women who underwent cesarean delivery and those with multiple pregnancies were excluded from the study. During the study period, there were 169,738 singleton vaginal deliveries, and 0.4% of the women suffered from PPF. Hypertensive disorders, induction of labor, dystocia of labor in the second stage, suspected fetal distress, meconium-stained amniotic fluid, postpartum hemorrhage, manual lysis of a retained placenta, and revision of the uterine cavity and cervix were found to be independently associated with PPF by multivariable analysis. Year of birth was found to be a risk factor for fever. Apgar scores lower than 7 at 1 but not 5 minutes were significantly higher in the PPF group. Perinatal mortality rates were significantly higher among women with PPF (6.7% versus 1.3%, odds ratio [OR] = 5.4; 95% confidence interval [CI] 3.9 to 7.3; P < 0.001). Using another multivariable analysis, with perinatal mortality as the outcome variable, PPF was found as an independent risk factor for perinatal mortality (OR = 2.9; 95% CI 1.9 to 4.6; P < 0.001). PPF in women undergoing vaginal deliveries is associated with adverse perinatal outcomes and specifically is an independent risk factor for perinatal mortality.     

Epidural analgesia and fetal head malposition at vaginal delivery

OBJECTIVE: To determine if nulliparas who delivered with on-demand epidural analgesia are more likely to have malpositioning of the fetal vertex at delivery than women delivered during a period of restricted epidural use. METHODS: A retrospective cohort of nulliparous women with spontaneous labor delivered during a 12-month period immediately before the availability of on-demand labor epidural analgesia was compared with a similar group of nulliparas delivered after labor epidural analgesia was available on request. The primary outcome variable was a non-occiput anterior position or malpositioned fetal head at vaginal delivery. RESULTS: The frequency of epidural use increased from 0.9% before epidural analgesia became available on demand to 82.9% afterward. Fetal head malpositioning at vaginal delivery occurred in 26 of 434 (6.0%) women delivered in the before period compared with 29 of 511 (5.7%) in the after period (relative risk 0.95, 95% confidence interval 0.6, 1.6). No statistically significant difference in the incidence of fetal head malpositioning was present after patients were stratified by mode of delivery (Mantel-Haenszel weighted relative risk 0.94, 95% confidence interval 0.6, 1.4). The study sample size provided 85% power to detect a two-fold increase in the incidence of fetal malpositioning from a baseline rate of 6% associated with on-demand epidural use. CONCLUSION: Providing on-request labor epidural analgesia to nulliparas in spontaneous labor did not result in a clinically significant increase in the frequency of fetal head malpositioning at vaginal delivery.     

Epidural analgesia in primigravidae in spontaneous labour at term: a prospective study

OBJECTIVES: To prospectively study the intervention rate, duration of labour, malpositions, fetal outcome, maternal satisfaction, voiding complications and adverse events in healthy primigravidae in spontaneous labour at term following epidural analgesia. METHODS: A prospective randomized study involving 55 patients in the epidural group and 68 in the control pethidine--inhalational entonox group. RESULTS: There were significantly more obstetric interventions (instrumental deliveries) in the epidural group (p < 0.01). The total duration of labour and the duration of the second stage was prolonged in the epidural group (p < 0.01). There were more malpositions at the second stage of labour in the epidural group (p < 0.02). There were no differences in fetal outcome (Apgar scores and Special Care Nursery admissions). Patients in the epidural group were consistently happier with their method of pain relief (p < 0.01). Two patients required blood patches while another 2 patients had persistent backache post epidural analgesia. CONCLUSION: Epidural analgesia in primigravidae in spontaneous labour at term led to an increased instrumental delivery rate, prolonged duration of labour, greater rate of malpositions in the second stage, increased oxytocin requirements but with no difference in fetal outcomes but with happier mothers as compared to the control group.     

Labor epidural analgesia in pre-eclampsia: a prospective study

AIM: To assess the safety of labor epidural analgesia in subjects with pre-eclampsia. METHODS: Nulliparous laboring women were included in the prospective study. One hundred pre-eclamptic nullipara who were given epidural analgesia (group I) were compared with 100 nullipara with pre-eclampsia who were not given epidural analgesia (group II). The outcome was further compared with 200 women who were not pre-eclamptic, but who were given epidural analgesia (group III), and also with 200 women who were normotensive and who were not given epidural analgesia (group IV). RESULTS: In group I, 58% of subjects delivered normally compared with 60% in group II. The operative vaginal delivery rate was 28% in group I compared with 24% in group II (P = 0.62), and the cesarean section rate was 14% and 16% in groups I and II, respectively, (P = 0.8). The difference was not statistically significant. The incidence of a prolonged second stage of labor was also not increased in pre-eclamptic women who received epidural analgesia. Five of the neonates in group I had a 5-min APGAR score <6 compared with seven neonates in group II. The necessity of neonatal resuscitation was also not significantly increased in group I (P = 1.0). The incidences of fetal distress (P = 0.71), non-progressive second stage of labor (P = 0.66) and cephalopelvic disproportion (P = 0.90) were not statistically different in the pre-eclampsia group compared with the non-pre-eclampsia group. Similar results were noted when these outcome measures were compared with the other two groups. With regard to hypotension and tachycardia in the pre-eclamptic subjects who were given epidural analgesia, no statistical difference (P = 0.72) was seen when compared with the normotensive subjects. CONCLUSION: In the absence of coagulopathy, epidural analgesia is a safe and effective method for labor pain relief, even for subjects with pre-eclampsia.     

Low concentration Ropivacaine in labor epidural analgesia. A prospective study on obstetric and neonatal outcome]

BACKGROUND: Epidural analgesia effectively alleviates labor pain. However controversy exists about the effect of epidural analgesia on labor outcome. The aim of this study is to assess the effect of a low concentration local anesthetic (ropivacaine 0.08%) in labor epidural analgesia (LEA) on labor pain relief, on the incidence of cesarean sections and instrumental vaginal deliveries, and on neonatal outcome. METHODS: In the period April 1998 - July 2000, 323 women in active labor with live, singleton and in vertex presentation fetuses at term of gestation were included in this prospective study. Women with pre-gestational and/or obstetric diseases or previous caesarean deliveries were excluded. One-hundred and five patients requiring - by written informed consent - LEA were allocated to receive standardised protocol of a low concentration local anesthetic (ropivacaine 0.08%) coadministered with opioid (sufentanil): ropivacaine group. The remaining 239 parturients who didn't require LEA were included in the control group. RESULTS: The demographic characteristics of the two groups were similar; 12 (10.4%) patients receiving LEA delivered by cesarean section, 17 (14.8%) by vacuum extractor whereas 86 (74.8%) had a spontaneous delivery. The risk of cesarean section (adjusted for age, BMI, parity, neonatal weight and gynecologist) resulted lower, even if not significantly, in the ropivacaine group (OR 0.9; 95% IC: 0.6-1.3), while a significant increased instrumental vaginal delivery rate has been reported, although little numbers reduce statistical significance. Neonatal outcome was unaffected by the use of LEA. CONCLUSIONS: The conclusion is drawn that a lower concentration of ropivacaine (0.08%) in LEA produces good labor pain relief with no detectable adverse effects on mother and neonate, and without significantly increasing cesarean section rate.     

Neonatal Outcome after Trial of Labor Compared with Elective Repeat Cesarean Section

ABSTRACT: Background: Trial of labor after cesarean section has been an important strategy for lowering the rate of cesarean delivery in the United States, but concerns regarding its safety remain. The purpose of this study was to evaluate the outcome of newborns delivered by elective repeat cesarean section compared to delivery following a trial of labor after cesarean. Methods: All low‐risk mothers with 1 or 2 previous cesareans and no prior vaginal deliveries, who delivered at our institution from December 1994 through July 1995, were identified. Neonatal outcomes were compared between 136 women who delivered by elective repeat cesarean section and 313 women who delivered after a trial of labor. To investigate reasons for differences in outcome between these groups, neonatal outcomes within the trial of labor group were then compared between those mothers who had received epidural analgesia (n = 230) and those who did not (n = 83). Results: Infants delivered after a trial of labor had increased rates of sepsis evaluation (23.3% vs 12.5%, p = 0.008); antibiotic treatment (11.5% vs 4.4%, p = 0.02); intubation to evaluate for the presence of meconium below the cords (11.5% vs 1.5%, p < 0.001); and mild bruising (8.0% vs 1.5%, p = 0.008). Within the trial of labor group, infants of mothers who received epidural analgesia were more likely to have received diagnostic tests and therapeutic interventions including sepsis evaluation (29.6% vs 6.0%, p = 0.001) and antibiotic treatment (13.9% vs 4.8%, p = 0.03) than within the no‐epidural analgesia group. Conclusions: Infants born to mothers after a trial of labor are twice as likely to undergo diagnostic tests and therapeutic interventions than infants born after an elective repeat cesarean section, but the increase occurred only in the subgroup of infants whose mothers received epidural analgesia for pain relief during labor. The higher rate of intervention could relate to the well‐documented increase in intrapartum fever that occurs with epidural use. (BIRTH 30:2 June 2003)     

A meta-analysis of upright positions in the second stage to reduce instrumental deliveries in women with epidural analgesia

BACKGROUND: Epidural analgesia is associated with an increased risk of instrumental delivery. We, in this study, present a systematic review in order to assess the effectiveness of maintaining an upright position during the second stage of labor to reduce instrumental deliveries among women choosing epidural analgesia. The study population included women with uncomplicated pregnancies at term with epidural analgesia established in the first stage of labor. METHODS: We searched MEDLINE, EMBASE, and CINAHL databases and the Cochrane Trials Register up to July 2003 and cross-checked the reference lists of published studies. Trial eligibility and outcomes were pre-specified. Group tabular data were obtained for each trial and were analyzed by using meta-analytic techniques. RESULTS: Only two studies were included with data on 281 women (166 upright and 115 recumbent). Upright positions in the second stage were associated with a non-significant reduction in the risk of both instrumental delivery (relative risk (RR) = 0.77, 95% confidence interval (CI) = 0.46-1.28) and cesarean section (RR = 0.57, 95% CI = 0.28-1.16). Both studies reported a statistically significant reduction in labor duration associated with upright positions. Data on other outcomes, including perineal trauma, postpartum hemorrhage, maternal satisfaction, and infant well-being, were insufficient. CONCLUSIONS: There were insufficient data to show a significant benefit from upright positions in the second stage of labor for women who choose epidural or to evaluate safety aspects. However the magnitude of the reductions in instrumental delivery and cesarean section warrants an adequately powered randomized, controlled trial to fully evaluate the practice of upright positions in the second stage for women with an epidural.     

Epidural analgesia and severe perineal tears: a literature review and large cohort study

Abstract

Objective: Our objectives were to study the association between epidural analgesia and risk of severe perineal tears (SPT), and identify additional risk factors for SPT.

Methods: We conducted a historical cohort study of women with term delivery between 2006 and 2011. Inclusion criteria were an uncomplicated singleton pregnancy, cephalic presentation and vaginal delivery. Multivariate logistic regression models were constructed to study the association between epidural analgesia and SPT, controlling for potential confounders. Additional models studied the association between prolonged second stage and instrumental labor and SPT.

Results: During the study period, 61?308 eligible women gave birth, 31?631 (51.6%) of whom received epidural analgesia. SPT occurred in 0.3% of births. Deliveries with epidural had significantly higher rates of primiparity, induction and augmentation of labor, prolonged second stage of labor, instrumental births and midline episiotomies. The univariate analysis showed a significant association between the use of epidural and SPT (OR: 1.78, 95% CI: 1.34–2.36); however, this association disappeared when parity was introduced (OR: 0.95, 95% CI: 0.69–1.29). Instrumental deliveries and prolonged second stage of labor were both strongly associated with SPT (ORs of 1.82 and 1.77)

Conclusions: Epidural analgesia was not associated with SPT once confounding factors were controlled for.     

Epidural analgesia: effects on labor progress and maternal and neonatal outcome

The intended and unintended effects of epidural labor analgesia are reviewed. Mothers randomized to epidural rather than parenteral opioid analgesia have better pain relief. Fetal oxygenation is not affected by analgesic method; however, neonates whose mothers received intravenous or intramuscular opioids rather than epidural analgesia require more naloxone and have lower Apgar scores. Epidural analgesia does not affect the rates of cesarean delivery, obstetrically indicated instrumented vaginal delivery, neonatal sepsis, or new-onset back pain. Epidural analgesia is associated with longer second labor stages, more frequent oxytocin augmentation, and maternal fever (particularly among women who shiver and women receiving epidural analgesia for > 5 hours) but not with longer first labor stages. Epidural analgesia has no affect but intrapartum opioids decrease lactation success. Epidural use and urinary incontinence are weakly, but probably not causally, associated. Epidural labor analgesia would improve if the mechanisms of these unintended effects could be determined.     

The effect of epidural analgesia on rates of episiotomy use and episiotomy extension in an inner-city hospital

OBJECTIVE: To determine the relationship between epidural analgesia and episiotomy usage and episiotomy extension in parturients delivering vaginally. METHODS: A database of 20 888 women experiencing spontaneous vaginal delivery at Grady Memorial Hospital from 1990 to 1995 was examined to identify those receiving epidural analgesia. Patients who underwent epidural catheter placement and had adequate perineal anesthesia at delivery comprised the epidural group, and all others comprised the control group. Demographic characteristics and obstetric outcomes were compared. Univariate and multivariate analyses were used to test the association between epidural analgesia, rates of episiotomy and episiotomy extension. RESULTS: Of the 20888 women experiencing spontaneous vaginal deliveries 6785 (32.5%) received epidural analgesia. Women receiving epidural analgesia were more likely than those not receiving epidural analgesia to be African-American and nulliparous, and to have an occiput posterior presentation. Women receiving epidural analgesia were also more likely to receive an episiotomy (27.8% vs. 13.1%, odds ratio (OR) 2.56, 95% confidence interval (CI) 2.38-2.75) and were less likely to experience a second-degree perineal laceration (11.6% vs. 14.4%, OR 0.75, 95% CI 0.69-0.82) or a third- or fourth-degree extension (8.9% vs. 12.4%, OR 0.81, 95% CI 0.68-0.97). When the results were adjusted for nulliparity, posterior presentation, macrosomia, shoulder dystocia and prolonged second stage, epidural analgesia remained independently associated with receipt of episiotomy (OR 1.97, 95% CI 1.88-2.06) and reduced episiotomy extension (OR 0.74, 95% CI 0.54-0.94). CONCLUSION: Epidural analgesia increases the rates of episiotomy use, and decreases the rate of episiotomy extension, independently of clinical factors associated with episiotomy.