观察硬膜外分娩镇痛对剖宫产术后阴道试产（TOLAC）母婴结局的影响。

对2010年8月至2017年5月在北京大学第一医院产科剖宫产术后拟阴道试产的103例产妇的围产期相关信息进行回顾性分析，采集包括产妇年龄、体质量指数、产前诊断、既往病史、产前血色素，最终分娩方式及产程时长，产程中是否人工破水、发热、使用催产素，新生儿Apgar评分，是否出现胎儿窘迫等病历资料。采用独立样本t检验比较是否经再次剖宫产终止妊娠的2组产妇之间产妇年龄、体质量质数（BMI）、距上次分娩时间、孕期、产前36周预估胎儿体质量、新生儿身长、新生儿体质量、产前血色素的差异，比较是否采用硬膜外麻醉的产妇第一、二产程时长的差异；采用秩和检验比较是否经再次剖宫产终止妊娠的2组产妇之间孕次的差异，比较是否采用硬膜外麻醉的婴儿Apgar评分之间的差异；采用χ²检验比较既往合并内科妇科病史、合并产科诊断、使用缩宫素、体温升高、人工破水、使用硬膜外分娩镇痛在是否经再次剖宫产终止妊娠的2组产妇之间的差异，比较是否采用硬膜外麻醉的产妇使用产钳助产几率、胎儿窘迫发生率以及进入新生儿重症监护室几率的差异。并对筛选出来的可能的影响因素进行多因素Logistic回归分析确定有剖宫产史的产妇行再次剖宫产终止妊娠的独立影响因素。

103例TOLAC的产妇中，23例经再次剖宫产终止妊娠（22.3%，23/103）。是否经再次剖宫产终止妊娠的2组产妇之间BMI［（29±5）kg/m² vs （27±3）kg/m²］、有既往妇科病史（13.0% vs 11.3%）以及使用硬膜外麻醉（13.0% vs 45.0%）方面比较，差异具有统计学意义（t=2.55，P=0.01；χ²=4.82，P=0.03；χ²=7.75，P<0.01）。产妇方面采用分娩镇痛者第一产程明显长于无分娩镇痛者［（543±231）min vs （316±211）min］，且差异具有统计学意义（t=4.59，P<0.001）；新生儿结局方面，采用硬膜外分娩镇痛者与非硬膜外镇痛者胎儿窘迫的发生率及出生后1 min、5 min Apgar评分比较差异均无统计学意义（P>0.05）。BMI是再次剖宫产的独立危险因素（β=0.164，P=0.03），而接受硬膜外分娩镇痛是再次剖宫产的独立保护因素（β=-1.600，P=0.02）。

硬膜外分娩镇痛可降低有剖宫产史产妇的再次剖宫产几率，但同时可增加剖宫产术后阴道分娩第一产程时长，对新生儿胎儿窘迫的发生率未见明显影响。

To observe the influence of epidural labor analgesia on the maternal and neonatal outcomes of trial of labor after cesarean section (TOLAC).

In this retrospective study, one hundred and three parturients who chose TOLAC at the Peking University First Hospital from August 2010 to May 2017 were enrolled. The perinatal information including age, BMI, prenatal diagnosis, past history, prenatal hemoglobin, mode of delivery, duration of delivery, ammiotomy, fever, use of oxytocin during labor, neonatal Apgar score, and the incidence of fetal distress was collected. The independent sample t-test was used to compare the differences in age, BMI, time after last birth, gestational age, prediction of fetal weight in 36 weeks prior to birth, neonatal length, neonatal weight, and prenatal hemoglobin between the two groups of subjects who underwent repeated cesarean section (RCS) or not. The t-test was used to compare the differences in duration of first and second stage of delivery between the two groups of subjects who accepted epidural labor analgesia or not. The rank sum test was used to compare the difference in gravidity between the two groups of subjects who undertaken RCS or not, and the Apgar score between the two groups of subjects who accepted epidural labor analgesia or not. The chi-square test was used to compare the difference in combined internal, gynecological, obstetrical diseases, oxytocin, fever, ammiotomy, and epidural labor analgesia between the two groups of subjects who undertaken RCS or not, and the incidence of forceps assisted delivery, neonatal distress, and admission to NICU between the subjects who accepted epidural labor analgesia or not. Multivariate logistic regression analysis was applied to investigate the relationship between perinatal factors including epidural labor analgesia and delivery mode of TOLAC.

Among the 103 parturients who chose TOLAC, 23 (22.3%) underwent RCS. Between the two groups of subjects who undertaken RCS or not, BMI [(29±5) kg/m² vs (27±3) kg/m², t=2.55, P=0.01], past gynecological diseases (13.0% vs 11.3%, χ²=4.82, P=0.03), and the rate of acceptance of epidural labor analgesia (13.0% vs45.0%, χ²=7.75, P<0.01) differed significantly. Among the parturients who underwent vaginal birth after cesarean section (VBAC), the use of epidural labor analgesia prolonged the first stage of labor [(543±231) vs (316±211), t=4.59, P<0.001]. The incidence of fetal distress and Apgar scores at 1 minute and 5 minutes did not differ significantly between the two groups of subjects who used epidural labor analgesia or not (P>0.05). BMI was identified to be an independent risk factor of RCS (β=0.164, P=0.03) while acceptance of epidural labor analgesia was an independent protective factor for RCS (β=-1.600, P=0.02).

Epidural labor analgesia can decrease the rate of RCS in women who have an earlier cesarean section but is accompanied by the prolonged first stage of labor. Using epidural labor analgesia has no obvious influence on the incidence of neonatal distress.