OC08.08: Fetal descent examined with transabdominal ultrasound

To predict vaginal delivery in nulliparous women with induced labour using fetal descent assessed with transabdominal ultrasound. This cohort study was conducted at Cairo University Hospital, Egypt and Parma University Hospital, Italy November 2022? to January 2024, and 93 nulliparous women with a single cephalic presentation at term were included before start of labour induction. Fetal head descent was assessed with transabdominal ultrasound as the suprapubic descent angle (SDA) between a longitudinal line through the symphysis pubis and a line from the upper part of the symphysis pubis extending tangentially to the fetal skull; like a mirror image of angle of progression (AoP). A small SDA represents a low fetal station. In all, 35/93 (38%) delivered vaginally (34 spontaneously and 1 with vacuum extraction) and 58/93 (62%) were delivered with Caesarean section. The SDA was successfully measured in all women. Mean SDA was 140 (SD 8.2) degrees, range 102-155 degrees. The area under the ROC curve was 89% (see figure 1) with 140 degrees as the best cut-off value. The sensitivity in predicting a vaginal delivery was 83%, false positive rate 21%, positive predictive value 71% and negative predictive value 88%. Using AoP as test variable, the area under the ROC-curve was 81%. Pearson correlation coefficient between SDA and AoP was 0.68 (95% CI 0.56-0.78). Fetal descent measured transabdominally as SDA is a promising method in predicting delivery mode before labour induction. Please note: The publisher is not responsible for the content or functionality of any supporting information supplied by the authors. Any queries (other than missing content) should be directed to the corresponding author for the article.