In this prospective, monocentric study, we investigated the potency of a novel three-dimensional (3D) body scanner for external pelvic assessment in birth planning for intended vaginal breech delivery. Between April 2021 and June 2022, 73 singleton pregnancies with intended vaginal birth from breech presentation (>36.0 weeks of gestation) were measured using a pelvimeter by Martin, a three-dimensional body scanner, and MR-pelvimetry. Measures were related to vaginal birth and intrapartum cesarean section. A total of 26 outer pelvic dimensions and 7 inner pelvic measurements were determined. The rate of successful vaginal breech delivery was 56.9%. The AUC (area under the curve) of the obstetric conjugate (OC) measured by MRI for predicting the primary outcome was 0.62 (OR 0.63; p = 0.22), adjusted for neonatal birth weight 0.66 (OR 0.60; p = 0.19). Of the 22 measured 3D body scanner values, the ratio of waist girth to maternal height showed the best prediction (AUC = 0.71; OR 1.27; p = 0.015). The best predictive pelvimeter value was the distantia spinarum with an AUC of 0.65 (OR = 0.80). The 3D body scanner technique is at least equal to predict successful vaginal breech delivery compared to MRI diagnostics. Further large-scale, prospective studies are needed to verify these results.
Keywords: MR-pelvimetry; birth planning; body scan; breech delivery; obstetric conjugate; three-dimensional pelvimetry.