The Exploratory Role of AI-Assisted Modelling in the Assessment of Labour Progress: The Value of Ultrasound Parameters Compared to Clinical Evaluation - Figure 1

Modern intrapartum ultrasound is characterised as a real-time, imaging-based assessment of the foetal head position, station, and descent during labour, usually performed transabdominally or transperineally (Fouché et al., 2012). The Angle of Progression (AoP) indicates the angle between the pubic symphysis and the leading portion of the foetal skull, demonstrating a strong correlation with the probability of vaginal delivery (Ghi et al., 2018; Youssef et al., 2021); the Head–Perineum Distance (HPD) (see Figure 1) is an external perineal measurement linked to the engagement and descent of the foetal head (Eggebø et al., 2008); and the Head–Symphysis Distance evaluates the proximity of the foetal head to the maternal pubic symphysis, serving as an additional indicator of foetal station (Barber et al., 2010; Kahrs & Eggebø, 2021). Intrapartum ultrasound, despite its benefits, has limitations such as reliance on operator expertise, variability in probe placement, diminished acoustic windows in instances of maternal obesity, and restricted availability in resource-limited environments (Barber et al., 2010; Fouché et al., 2012).