剖宫产后阴道分娩的风险评估研究

Cesarean section delivery not only increases the burden of national health care, but also can harm to the maternal and child health. After implementation of the "two-child policy for only-child parent" policy in the future, more than one million number of repeated cesarean section will add annually in China. This will become a new public health problem. Vaginal Birth After Cesarean (VBAC) can reduce the rate of repeat cesarean section, however there is no VBAC risk assessment tool in China at present. On the basis of previous studies on the influence factors of cesarean delivery, a multi-center retrospective cohort study will be conducted as follows. Data for all deliveries from 9 research centers between a 10-year periods (2006.1-2015.12) will be reviewed. Variables associated with successful VBAC and modes of delivery will be collected, including uterine scar thickness, cervical examination, maternal age, pregnancy complications and so on. Women with one previous cesarean delivery and one subsequent delivery are included. Influence factors associated with successful VBAC are identified using multivariable logistic regression. The model will be evaluated using Bootstrap validation and ROC. Points are assigned to these characteristics and the VBAC score is correlated with VBAC success rate. Finally, a VBAC risk assessment tool will be created. This study aims to provide clinical consultation and clinical decision-making for women who want to select VBAC delivery. In addition, this result can be useful to reduce the rate of repeat cesarean section, to reduce the burden of health care and to promote maternal and child health.

剖宫产分娩不但会增加国家医疗负担，也会给母婴健康带来严重危害。“单独二孩”政策实施以后，我国每年将新增100万重复剖宫产的产妇，这将成为新的公共卫生问题。剖宫产后阴道分娩（VBAC）可以降低重复剖宫率，但是国内目前还没有VBAC风险评估工具。本研究在前期对剖宫产分娩影响因素研究的基础上，拟采用多中心回顾性队列研究方法，以2006.01至2015.12十年期间在全国9个研究中心生育过二胎的产妇为研究对象（其第一胎为剖宫产分娩），收集第二胎分娩时子宫疤痕厚度、宫颈成熟度、孕妇年龄和妊娠并发症等信息以及第二胎的分娩方式；分析影响VBAC分娩的因素；建立多水平Logistic回归预测模型，并采用Bootstrap法联合ROC曲线对模型进行评价；最后建立适合我国计划生育国情的VBAC风险评估工具。为意愿VBAC分娩的产妇提供临床咨询和决策，为降低重复剖宫产率、降低疾病负担和促进母婴健康提供科学依据。

剖宫产分娩不但会增加国家医疗负担，也会给母婴健康带来严重危害。“单独二孩”政策实施以后，我国每年将新增100万重复剖宫产的产妇，这将成为新的公共卫生问题。剖宫产后阴道分娩（VBAC）可以降低重复剖宫率，但是国内目前还没有VBAC风险评估工具。本研究在前期对剖宫产分娩影响因素研究的基础上，拟采用多中心回顾性队列研究方法，以2006.01至2015.12十年期间在全国9个研究中心生育过二胎的产妇为研究对象（其第一胎为剖宫产分娩），收集第二胎分娩时子宫疤痕厚度、宫颈成熟度、孕妇年龄和妊娠并发症等信息以及第二胎的分娩方式；分析影响VBAC分娩的因素；建立多水平Logistic回归预测模型，并采用Bootstrap法联合ROC曲线对模型进行评价；最后建立适合我国计划生育国情的VBAC风险评估工具。为意愿VBAC分娩的产妇提供临床咨询和决策，为降低重复剖宫产率、降低疾病负担和促进母婴健康提供科学依据。本次研究结果发现：1）VBAC率为70.5%（210/298）；子宫破裂发生率为2.7%（8/298），产后出血发生率9.4%（28/298），新生儿窒息发生率为1.3%（4/298）；无孕产妇及围产儿死亡；2）单因素分析结果显示，孕妇的年龄、孕前BMI、临产时子宫颈Bishop评分、是否引产、分娩孕周及新生儿出生体质量是VBAC的影响因素；VBAC孕妇的年龄和临产时子宫颈Bishop评分明显高于TOLAC失败者（P<0.05），而孕前BMI、引产率、分娩孕周及新生儿出生体质量明显低于TOLAC失败者（P<0.05）；3）logistic多因素回归分析结果显示，孕妇年龄、孕前BMI、临产时子宫颈Bishop评分及新生儿出生体质量是VBAC的主要影响因素（P<0.05）。因此我们认为，孕妇年龄、孕前BMI、临产时子宫颈Bishop评分和新生儿出生体质量是影响VBAC的主要因素。