Head Perineal Distance and Angle of Progression to Predict Caesarean Delivery due to Labor Dystocia in Term Pregnancy with Active Phase of Labor
Teenat Kanjanasignh MD1, Wiyada Luangdansakul MD1
Affiliation : 1 Department of Obstetrics and Gynecology, Bhumibol Adulyadej Hospital, Bangkok, Thailand
Objective : To evaluate the predictive value of head perineal distance [HPD] and angle of progression [AOP] measured by transperineal
ultrasound to predict of caesarean delivery due to labor dystocia in term pregnancy with active phase of labor.
Materials and Methods : The present report was a prospective study conducted at Bhumibol Aduyadej Hospital between January
and December 2016. Term singleton pregnancy in cephalic presentation were enrolled when they entered the active phase of labor
and abnormal partograph were not present during the time of enrollment. HPD and AOP were measured and then all participants
received standard labor management. Data of transperineal ultrasound and obstetric outcome were obtained and analyzed to
predict caesarean delivery due to labor dystocia.
Results : Among 400 participants enrolled in the present study, sixty-three cases (15.75%) underwent caesarean delivery due to
labor dystocia. From the receiver operating characteristics curve, area under the ROC curve of HPD and AOP to predict cesarean
delivery were 66% (95% CI, 59% to 73%) and 74% (95% CI, 68% to 80%), respectively. The cut-off point of HPD was 5.67 cm
or greater, corresponding to a sensitivity of 88.69%, and a speci(cid:976)icity of 34.42%. For AOP, 96 degrees or less, corresponded to a
sensitivity of 71.42%, a speci(cid:976)icity of 67.46%. According to binary logistic regression, AOP was associated with caesarean delivery
due to labor dystocia signi(cid:976)icantly and independently [adjusted OR 4.46 (95% CI 2.06 to 9.21)], while the HPD was not [adjusted
OR 1.80 (95% CI 0.72 to 4.51)].
Conclusion : AOP of 96 degrees or less can be used as a screening tool for labor dystocia in term pregnancy while the HPD cannot.
Keywords : Labor dystocia, Head perineal distance, Angle of progression
