剖宫产术后再次妊娠分娩方式的 Fisher 判别

目的：应用Fisher判别法归类剖宫产术后再次妊娠的分娩方式，为剖宫产史（ PCS）孕妇分娩方式的选择提供参考。方法以愿意阴道试产的216例 PCS 孕妇为研究对象，采集年龄、职业、临产前体重指数（ BMI）、距前次剖宫产时间、妊娠并发症、超声测量胎儿腹围、胎儿双顶径、子宫下段厚度、胎儿性别，记录分娩中Bishop宫颈成熟评分、宫缩剂应用情况等。结果①分娩方式：阴道自然分娩成功66例，阴道助产分娩成功58例，剖宫产分娩92例。②单因素分析显示：3种分娩方式在职业、临产前BMI、胎儿腹围、双顶径、宫缩剂应用、距前次剖宫产时间、子宫下段厚度和Bishop评分方面差异有统计学有意义，P＜0．05。③逐步法Fisher判别入选判别函数的因素是胎儿腹围（ X1）、子宫下段厚度（ X2）、Bishop评分（ X3）和应用宫缩剂（ X4）。 Fisher判别函数：Function 1＝-0．101X1＋2．202X2＋0．649X3＋0．289X4-9．243；Function 2＝0．258X1-0．156X2＋0.593X3＋0．409X4-14．384。④函数预测阴道顺产、阴道助产和剖宫产的敏感性分别是80．30％、56．90％和78．26％，总体符合率为73．15％。结论胎儿腹围、子宫下段厚度、Bishop评分和应用宫缩剂是影响PCS孕妇阴道分娩成败的重要因素。以此4项指标建立的Fisher判别函数可为PCS孕妇分娩方式的选择提供中等强度诊断效能。

The Fisher Discriminant of Pregnancies after Cesarean Section

Objective To classify the pregnancies after cesarean section by using Fisher discriminant in order to provide a reference mode of delivery in pregnant women with the history of cesarean section （ PCS ） . Methods 216 cases of PCS pregnant women with vaginal delivery were applied in this study .Age, occupation , labor before the body mass index （ BMI） , the time from a previous cesarean section , complications of pregnan-cy, fetal abdominal circumference , fetal biparietal diameter , the lower uterine segment thickness , the sex of a fetus, the Bishop cervical ripening score , and the application of contraction agent were collected .Results ①The mode of delivery：Vaginal delivery was successful in 66 cases.Vaginal midwifery delivery was successful in 58 cases.Cesarean section delivery was successful in 92 cases.②Single factor analysis showed：The three kinds of mode of delivery has statistically significantat in occupation , preclinical BMI , fetal abdominal circum-ference , biparietal diameter , application , tocolytic agents from the previous cesarean section time , lower uter-ine segment thickness and Bishop score , P〈0.05.③The selected discriminant factors were the fetal abdomi-nal circumference （ X1 ） , the lower uterine segment thickness （ X2 ） , Bishop score （ X3 ） and the application of of oxytocin （ X4 ） by stepwise Fisher discriminant function .Fisher discriminant function： Function 1 =-0. 101X1＋2.202X2 ＋0.649X3 ＋0.289X4 -9.243;Function 2=0.258X1 -0.156X2 ＋0.593X3 ＋0.409X4 -14 .384 .④The sensitivity of spontaneous vaginal delivery , vaginal delivery and cesarean section is respectively 80.30%, 56.90%and 78.26% by Function prediction.Overall compliance rate was 73.15%.Conclusion Fetal abdominal circumference , the lower uterine segment thickness , Bishop score and application of tocolytic agents are the main factors affecting the success of PCS pregnant women with vaginal delivery .It can provide a moderate diagnostic efficacy for PCS pregnant women with vaginal delivery based on the four indexes of Fisher discriminant function .