经会阴超声动态监测胎头方向角联合头-会阴距离对剖宫产术后再妊娠阴道试产的预测价值OA

Objective:To explore predictive value of trans-perineal dynamic monitoring of ultrasound on direction of fetal head angle(FHA)combined with head-perineum distance(HPD)for trial of labor after cesarean(TOLAC).Methods:A prospective study was conducted on 80 pregnant women whose single fetal were head position,who met the TOLAC signs and admitted to the First Hospital of Dongguan Affiliated to Guangdong Medical University between January 2022 and May 2024.A standardized ultrasound protocol was used to dynamically monitor FHA and HPD at 5 cm and 8 cm of cervical dilatations,and before the second stage of labor.Participants were subsequently divided into two groups based on the final delivery mode:successful vaginal birth after cesarean(VBAC)group(n=56)and repeat cesarean section(RCS)group(n=24).Receiver operating characteristic(ROC)curves were plotted,and the area under curve(AUC)of ROC curve was calculated.The efficacy was predicted by using parameters of multivariate logistic regression analysis.Results:When cervical dilatation was 5 cm,the mean FHA was(97.52±4.73)° in the VBAC group,which increased 13.21° than(84.31±4.25)° in the RCS group,showing a statistically significant difference(t=11.786,P<0.05).When cervical dilatation was 8 cm,the mean FHA was(88.93±4.85)° in the VBAC group,which increased 13.31° than(75.62±4.42)° in the RCS group,and the difference was significant(t=11.540,P<0.05).The HPD values of the VBAC group were significantly shorter than those of the RCS group when cervical dilatation was both 5 cm and 8 cm(t=3.642,4.127,P<0.05).The average change rate of HPD in VBAC group was(6.32±1.45)mm/h,which was faster 2.43 mm/h than(3.89±1.27 mm/h)in RCS group,and the difference was significant between two groups(t=3.892,P<0.05).Multivariate analysis identified"FHA≥87.8°"and"HPD≤44.5 mm"were independent predictors for VBAC(OR=4.58,3.38,P<0.05).The combination of FHA and HPD demonstrated optimal predictive performance at 8 cm of cervical dilatation,which AUC value,sensitivity and specificity were respectively 0.892,84.2%and 81.5%.The ratio of the history of prior labor stagnation of the RCS group was higher than that of the VBAS group,and there was significant difference between two groups(x2=4.732,P<0.05).There were statistically significant differences were observed between two groups regarding to age,gestational weeks,and other indicators at baseline(P>0.05).Conclusion:Dynamic monitoring of FHA and HPD can effectively predict delivery outcomes in pregnancy after cesarean section(PACS).The combination of FHA and HPD exhibits the best predictive efficacy at the cervix and nearly the entire stage.