Angle of progression measured using transperineal ultrasound for prediction of uncomplicated operative vaginal delivery: systematic review and meta-analysis

Intrapartum transperineal ultrasound: angle of progression to evaluate and predict the mode of delivery and labor progression

Intrapartum ultrasonography serves as a valuable tool for the objective evaluation of labor progression and effectively identifies underlying factors, such as asynclitism, in cases of abnormal labor progression. Among the various ultrasound measurement techniques, the angle of progression (AOP) demonstrates favorable reproducibility and accuracy in assessing fetal head descent. In the context of abnormal labor, interventions differ across different stages of labor, emphasizing the importance of investigating the utility of AOP according to labor stages in this review article. Pre-labor assessment of AOP can be beneficial in terms of counseling for the timing of induction of labor, while a wider AOP value during the prolonged first stage of labor has demonstrated a positive correlation with successful vaginal delivery and shorter time to delivery. In the second stage of labor, the AOP has exhibited efficacy in predicting the mode of delivery and complicated operative deliveries. Furthermore, it has assisted in predicting the duration of labor, thereby highlighting its potential as a decision-making model for labor progression. However, further research is needed to investigate aspects, such as the determination of cutoff values, of AOP, considering the multifaceted characteristics of labor progression, which are influenced by complex interactions among maternal, fetal, and other contributing factors.

Visual biofeedback for shortening second stage of labor: randomized controlled trial

OBJECTIVE

To determine whether visual biofeedback can be used during labor as an effective tool for shortening the second stage of labor and reducing the need for instrumental delivery.

METHODS

This was a single-center randomized controlled trial. Nulliparous women under epidural anesthesia were randomized at the point of full dilation into the biofeedback group (n = 50) or the control group (n = 50). Both groups received coached maternal pushing during four consecutive contractions, while an experienced obstetrician performed transperineal ultrasound. Only women in the biofeedback group observed the ultrasound display screen. Following this intervention, labor was managed routinely by the obstetric team. Angle of progression (AOP) was measured at rest and while pushing, before and during the first and fourth contractions. Second-stage duration and delivery outcomes were compared between groups.

RESULTS

Visual biofeedback did not affect the duration of the second stage, which lasted for a median of 2.28 (interquartile range (IQR), 1.25-3.10) h in the biofeedback group vs 2.08 (IQR, 1.58-3.02) h in the control group (P = 0.981). AOP was significantly higher in the biofeedback group compared with the control group, both at rest before the fourth contraction (mean ± SD, 142.6° ± 15.9° vs 136.8° ± 13.1°; P = 0.049) and while pushing during the fourth contraction (mean ± SD, 159.3° ± 19.2° vs 149.4° ± 15.1°; P = 0.005). The increase in AOP was significantly higher in the biofeedback compared with the control group between rest and pushing at the last push (mean ± SD, 16.6° ± 11.0° vs 12.6° ± 8.3°; P = 0.041) and between the first rest and last push (mean ± SD, 24.4° ± 13.6° vs 17.9° ± 11.3°; P = 0.011). The rate of intact perineum was similar between groups (12% vs 8%; P = 0.505).

CONCLUSIONS

Visual biofeedback during the second stage of labor may facilitate descent of fetal head during maternal pushing without affecting second-stage duration, possibly due to the short duration of the intervention. Future studies should focus on continuous intervention throughout the second stage of labor. © 2023 International Society of Ultrasound in Obstetrics and Gynecology.

Intrapartum ultrasound and mother acceptance: A study with informed consent and questionnaire

Introduction

Intrapartum ultrasound (IU) is used in the delivery ward; even if IU monitors the labouring women, it could be perceived as a discomfort and even as an" obstetric violence", because it is a young technique, not often well "accepted". A group of clinicians aimed at obtain an informed consent from patients, prior to perform a translabial ultrasound (TU). The aim of this study was to evaluate the acceptance of both translabial and transabdominal IU.

Methods

In this study, performed at the University Hospital of Bari (Unit of Obstetrics and Gynecology), were enrolled 103 patients in the first or second stage of labor in singleton cephalic presentation. A statistical frequency and an association analysis were performed. As a significant result, we consider the peace of mind/satisfaction and the" obstetric violence". IU was performed both transabdominal and translabial to determine the presentation, head positions, angle of progression and head perineum distance. During the first and second stage of labor, the ASIUG questionnaires (Apulia study intrapartum ultrasonography group) were administered.

Results

74 (71, 84%) patients underwent IU and 29 had a vaginal examination (28, 15%). Significant less "violence" has been experienced with a IU (73 out 74/98, 65%) and only one person (1 /1, 35%) recorded that. On the contrary, 10 patients (10/29) perceived that "violence" (34, 48%) while 19 (65, 52%) did not respond on a similar way, after a vaginal examination (VE). More patients felt satisfaction (71 out 74/95, 95%) with the use of IU and only 3 (3/4, 05%) felt unease. A different picture was evident in the vaginal examination group. Only 17 patients (17 out 29/58, 62%) felt comfort while 12 (41, 38%) felt unease.

Conclusions

In our study, IU use is well accepted by most of patients, because it could reassure women about their fetal condition. Moreover, they can see the fetus on the screen, while the obstetrician is performing the US and this is important for a visual feedback, in comparison with the classical VE.