Intrapartum monitoring of the fetal heart rate using transabdominal electrocardiography: A reliability and accuracy study

Introduction: In this study, we evaluated the performance of an intrapartum monitoring system (the TOCONAUTE) for fetal heart rate estimation using transabdominal electrocardiography. Method: This prospective study was conducted in Lille University Hospital's maternity ward between August 2022 and November 2023 to assess the performance of the TOCONAUTE compared to a cardiotocograph (CTG). Pregnant women in labor at 36 weeks or more of gestation with a singleton in cephalic presentation were eligible for enrollment in the study. In addition to the cardiotocograph, the participants received an abdominal electrode patch after providing their written informed consent. The positive percent agreement with the cardiotocograph indicated reliability, and the Bland-Altman analysis determined accuracy. Results: Of the 60 patient recruited, 35 patients were included in the recording analysis. The recordings had a mean duration of 519 f 210 min. The TOCONAUTE's fetal heart rate (FHR) overall positive percent of agreement (PPA) was 84.2 f 10.4 %. The PPA was greater than 80 % for all labor phases, except for expulsion (44.7 %). The overall mean bias was 1.7 f 2.4. For the FHR, the mean bias was lower than 2 bpm for all labor phases, except for expulsion (14.13 f 15.04 bpm). Conclusion: Compared with traditional CTG, this study demonstrated the TOCONAUTE's reliability and accuracy for FHR estimation in all labor phases except expulsion.