限制会阴切开在巨大儿经阴道分娩中的应用

目的：探讨限制会阴切开在巨大儿头位经阴道分娩中的应用，比较其实施前后母儿的结局。方法收集2013年1月至2015年6月经阴道分娩的533例单胎头位巨大儿孕妇的临床资料进行回顾性分析，将其中行限制会阴切开的295例患者纳入观察组，将其中未行限制会阴切开的238例患者纳入对照组，比较两组母儿的妊娠结局。结果两组产妇第二产程时间、产时出血量、产后2h出血量均无显著性差异（t值分别为1．458、0．457、0．512，均P＞0．05）。观察组会阴切开率为62．04％（183／295），对照组会阴切开率为76．89％（183／238），观察组显著低于对照组（χ2＝24．236，P＜0．01），两组会阴裂伤、会阴完整发生率均无显著性差异（χ2值分别为4．379、2．901，均P＞0．05）。观察组产妇的盆底肌力略差于对照组，但两组I类肌纤维肌力、Ⅱ类肌纤维肌力均无显著性差异（χ2值分别为2．568、1．296，P＞0．05）。两组新生儿均未发生重度窒息，观察组发生6例（2．03％）轻度新生儿窒息，对照组发生5例（2．10％）；观察组发生2例（0．07％）新生儿产伤（臂丛神经损伤和锁骨骨折），对照组发生2例（0．08％）。将两组新生儿轻度窒息率和产伤发生率相比较，观察组的并发症略低于对照组，但差异无统计学意义（χ2值分别为4．560、5．112，均P＞0．05）。结论限制会阴切开不增加巨大儿产妇严重会阴裂伤与新生儿窒息率，且不延长产程，巨大儿经阴道分娩过程中，应进行动态、持续、准确的母儿评估，在保证母儿安全的前提下，有经验的助产人员应尽量降低会阴切开率。

Application of restrictive episiotomy in vaginal delivery of macrosomia

Objective To explore the application of restrictive episiotomy (RE) in vaginal delivery of macrosomia and to compare the maternal and neonatal results before and after RE.Methods A retrospective analysis was carried out on the clinical data of 533 cases of single macrosomia fetal through vaginal delivery from January 2013 to June 2015.The patients (n=295) with RE in vaginal delivery were taken into observation group, and the patients ( n =238 ) who did not take RE were in control group.Two groups were compared in maternal and neonatal outcomes.Results There were no significant differences in second stage of labor, intraoperative bleeding volume, and bleeding volume 2h after delivery between two groups (t value was 1.458, 0.457 and 0.512, respectively, all P>0.05).The rate of episiotomy in the observation group was 62.04%(183/295), which was lower than that in the control group (76.89%, 183/238) (χ2 =24.236, P<0.01).There was no significant difference in the incidence of perineal laceration and perineum complete rate (χ2 value was 4.379 and 2.901, respectively, both P>0.05).In the observation group maternal pelvic floor muscle strength was slightly poorer than that in the control group, but two groups were not significantly different in type I muscle fibers strength and type II muscle fiber strength (χ2 value was 2.568 and 1.296, respectively, both P>0.05).No severe asphyxia was found in either group, and there were 6 mild cases (2.03%) and 5 mild cases (2.10%) of asphyxia in the observation group and the control group, respectively.Two cases (0.07%) of birth trauma (brachial plexus injury and fracture of clavicle) were found in the observation group and 2 cases (0.08%) in the control group.Comparing the incidence of mild asphyxia and birth trauma in two groups, the complications in the observation were slightly fewer than the control group, but the difference was not significant (χ2 value was 4.560 and 5.112, respectively, both P>0.05).Conclusion RE will not increase the incidence of severe perineal laceration and neonatal asphyxia among macrosomia delivery, and the stage of labor will not extend.In the process of macrosomia delivery through vaginal delivery, dynamic, continuous and accurate assessments should be made both for mothers and neonates.Under the condition of ensuring safety of mother and neonates, experienced midwives should try to reduce the rate of perineal incision.