Evaluation of Power of Intrapartum Ultrasonography to Predict Obstetric Outcomes in Pregnant Women with a Prolonged Second Stage of Delivery

Abstract

Introduction-Aim: Digital pelvic examination (DPE), which is used to monitor the progression of delivery; has 5 parameters: dilation, effacement, consistency and position of cervix and level-or station, of the fetal head. All these parameters are subjective and unrepeatable. In this study, it was aimed to evaluate the success of using intrapartum ultrasonography (IUSG) in the second stage of delivery to predict the obstetric outcomes.

Materials and Methods: 811 pregnant women, aged between 17 and 45 were included in the study. A detailed VM was made to all participants, who reached full cervical opening. After the effacement, position and consistency of the cervix, the level and the position of the fetal head and the state of the membranes were determined, these VE findings were confirmed by intrapartum ultrasonography. IUSG evaluations were performed by translabial and / or suprapubic method. Fetal occiput-spin angle (OSA) was evaluated by the suprapubic method and head-symphysis distance (HSD), head-perineum distance (HPD), head rotation (HR), head direction (HD), progression angle (AoP), progression distance (PD) and pelvic arch angle (PAA) were evaluated by translabial method. DPE and IUSG evaluations of all 810 participants were made by a single observer.

Results: A total of 810 participants were included in the study, including 494 primiparas and 316 multiparas; 520 were Turkish, 258 Syrian and 32 Meskhetian. There was no statistically significant difference in the distribution of parity by races or in the rates of delivery types between races. The duration of the second stage of delivery was significantly longer in Turkish and Syrian primiparas and multiparas women who underwent operative delivery (OD), including IVD and CS. In all three races, the most frequent fetal head position was left occiput transverse (LOT), and fetal head position was significantly associated with the type of delivery in primiparas subgroups.

Some of the eight intrapartum ultrasonographic parameters we examined were found to have clinical significance in predicting clavicle fracture. HR, HD, PD, and OSA were successful in predicting clavicle fracture in spontaneous vaginal delivery; HR and AoP were successful in predicting clavicle fracture in instrumental vaginal delivery. For spontaneous vaginal delivery, increased HR and PD, and decreased HD and OSA were associated with an increased incidence of clavicle fracture. In instrumental vaginal delivery, increased HR and AoP were observed to be associated with increased clavicle fracture rates.

Conclusion: In our study it was concluded that performing IUSG, regardless of DPE, can be very useful in clinical practice. The data obtained through IUSG, especially in the second stage of delivery; enabled visualization of complex positional changes occurring at the fetal head during its progress in the birth canal and made it possible to be a more objective follow-up for delivery process compared to the VM. It is thought that the standardization of the data obtained with ITU and IUSG can provide a clearer illumination of the pathophysiology of abnormal delivery. Thus, especially in complicated by dystocia delivery, clinical advantage can be gained in predicting delivery arrest and operative delivery, and maternal and neonatal adverse outcomes can be prevented during and after the delivery.