Visual Biofeedback (VB) through Trans-Perineal Ultrasound (TPU) during the active second stage of labor to improve maternal childbirth satisfaction: protocol of a randomized controlled trial

Abstract Background Childbirth can be psychologically traumatic for up to 44% of women. Determinants of a negative childbirth experience include loss of control and lack of emotional support or interaction with obstetric caregivers. Vaginal childbirth also predisposes to somatic trauma, including trauma to the pelvic floor and perineum, which may lead to pelvic floor dysfunctions (PFDs). Providing Visual Biofeedback through Trans-Perineal Ultrasound (VB-TPU) during the expulsive phase of labor has been shown to increase efficacy of pushing efforts and may reduce perineal trauma. The primary aim of this trial is to investigate the effect of VB-TPU, initiated at the onset of the active second stage, on maternal childbirth satisfaction. The hypothesis is that VB-TPU will enhance the mother’s sense of control and patient-caregiver communication, and ultimately maternal satisfaction with childbirth. Methodology Monocentric randomized controlled trial (RCT) conducted in the Department of Obstetrics and Gynecology at the University Hospitals of Leuven, Belgium. Nulliparous term pregnant women with fetuses in cephalic presentation and undergoing labor with epidural analgesia will be included. The intervention consists of VB-TPU initiated at the active second stage for ten consecutive contractions. The control group will undergo verbal coaching and digital vaginal examinations to assess fetal head descent, as per standard of care. Randomization (n = 488) and group allocation (1:1 ratio) will take place at the onset of the second stage, with stratification according to sonographic fetal head position and descent. The primary endpoints are Birth-Satisfaction-Scale-Revised (BSS-R) questionnaire scores assessed two days after delivery, and the incidence and severity of perineal trauma. Exploratory endpoints are (1) BSS-R scores 12 weeks postpartum, (2) the incidence and severity of PFDs 12 weeks and 6–12 months postpartum, (3) the efficacy of maternal pushing efforts, and (4) the incidence and severity of pelvic floor muscle trauma, diagnosed 12 weeks and 12 months postpartum by pelvic floor ultrasound. Discussion This RCT will provide evidence on the effect of ultrasound-guided maternal pushing during the expulsive phase of labor on maternal childbirth satisfaction and perineal trauma as primary outcomes. Trial registration Clinicaltrials.gov (NCT06847308, registration date 2025-02-26).