ABSTRACT
OBJECTIVES: Well-established clinical practice for assessing progress in labor involves routine abdominal palpation and vaginal examination (VE). However, VE is subjective, poorly reproducible and painful for most women. In this study, our aim was to evaluate the feasibility of systematically integrating transabdominal and transperineal ultrasound assessment of fetal position, parasagittal angle of progression (psAOP), head-perineum distance (HPD) and sonographic cervical dilatation (SCD) to monitor the progress of labor in women undergoing induction of labor (IOL). We also aimed to determine if ultrasound can reduce women's pain during such examinations. METHODS: Women were recruited as they presented for IOL in three maternity units. Ultrasound assessments were performed in 100 women between 37 + 0 and 41 + 6 weeks' gestation. A baseline combined transabdominal and transperineal scan was performed, including assessment of fetal biometry, umbilical artery and fetal middle cerebral artery Doppler, amniotic fluid index, fetal spine and occiput positions, psAOP, HPD, SCD and cervical length. Intrapartum scans were performed instead of VE, unless there was a clinical indication to perform a VE, according to protocol. Participants were asked to indicate their level of pain by verbally giving a pain score between 0 and 10 (with 0 representing no pain) during assessment. Repeated measures data were analyzed using mixed-effect models to identify significant factors that affected the relationship between psAOP, HPD, SCD and mode of delivery. RESULTS: A total of 100 women were included in the study. Of these, 20% delivered by Cesarean section, 65% vaginally and 15% by instrumental delivery. There were no adverse fetal or maternal outcomes. A total of 223 intrapartum ultrasound scans were performed in 87 participants (13 women delivered before intrapartum ultrasound was performed), with a median of two scans per participant (interquartile range (IQR), 1-3). Of these, 76 women underwent a total of 151 VEs with a median of one VE per participant (IQR, 0-2), with no significant difference between vaginal- or Cesarean-delivery groups. After excluding those with epidural anesthesia during examination, the median pain score for intrapartum scans was 0 (IQR, 0-1) and for VE it was 3 (IQR, 0-6). Cesarean delivery was significantly associated with a slower rate of change in psAOP, HPD and SCD. CONCLUSIONS: Comprehensive transabdominal and transperineal ultrasound assessment can be used to assess progress in labor and can reduce the level of pain experienced during examination. Ultrasound assessment may be able to replace some transabdominal and vaginal examinations during labor. © 2024 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.
ABSTRACT
OBJECTIVES: To determine the rate of pelvic floor trauma, levator ani muscle (LAM) avulsion as well as the mean difference in levator hiatus area, after normal vaginal deliveries (NVD) and vacuum assisted deliveries (VD), assessed with three-dimensional transperineal ultrasound (3D-TpUS). MATERIALS AND METHODS: Prospective observational study with 151 nulliparous women with NVD or VD at ≥37 weeks between 9-2012 and 6-2013. 3D-TpUS was performed six months after every patient's delivery, during which LAM, anteroposterior diameter, transverse diameter and levator hiatus area were assessed. RESULTS: A total of 146 nulliparous were studied, comprising 73 NVD and 73 VD. No differences in obstetric, intrapartum or neonatal characteristics were observed between study groups, with the following exceptions: maternal age (28.1 ± 5.4 versus 30.4 ± 5.5; p = 0.008, OR = 1.1) and episiotomy rate (35.6% versus 97.3%; p = 0.011, OR = 4.3). LAM avulsion rate was 9.6% in NVD versus 34.2% in VD (p = 0.001, OR 3.99), while levator hiatus area at rest was 16.5 ± 3.2 versus 18.2 ± 3.9 (p = 0.016). CONCLUSIONS: Vacuum assisted deliveries present a higher rate of LAM avulsion, as well as a greater increase in levator hiatal area than in NVD.