Study on the Application Results of a Flexible Wearable Fetal-Maternal Heart Rate Monitor During Labor

Abstract Purpose Conventional fetal heart rate monitoring during labor has disadvantages, such as restricting maternal movement and the risk of supine hypotension. This study aimed to evaluate the reliability and safety of a flexible wearable fetal–maternal heart rate monitor, and its impact on the healthcare providers’ and maternal satisfaction. Methods A quasi-experimental design based on convenience sampling was employed to recruit 106 women with singleton pregnancies who were hospitalized and gave birth at Beijing Tsinghua Changgung Hospital between June 2022 and June 2023. The participants were monitored simultaneously using a conventional Doppler fetal heart rate monitor (control group) and a flexible, wearable fetal–maternal heart rate monitor (experimental group) during the onset of labor. Fetal heart rate and uterine contraction data were collected from both monitoring systems throughout labor. In addition, questionnaires were administered to evaluate the satisfaction of healthcare providers and participants with the respective devices. Results A total of 79 paired fetal heart rate measurements and 49 paired uterine contraction frequency and intensity measurements were analyzed. No significant difference was observed between the flexible and conventional monitoring devices for fetal heart rate (142.86 ± 9.40 vs. 143.66 ± 9.79 bpm, P = 0.0826). Bland–Altman analysis demonstrated a mean bias of -0.80 bpm, with 95% limits of agreement ranging from − 7.68 to 6.09 bpm, and no significant proportional bias ( P = 0.3281). Uterine contraction frequency was also comparable between the two devices ( P = 0.865), with a mean bias of 0.28 and 95% limits of agreement from − 3.03 to 3.59, although significant proportional bias was detected ( P = 0.0021). In contrast, uterine contraction intensity measured by the flexible device was significantly lower than that measured by the conventional device ( P = 0.0001), with a mean bias of -20.71 and wide 95% limits of agreement (-82.19 to 40.76); significant proportional bias was also observed ( P = 0.0009). Conclusion Compared with conventional fetal monitoring, flexible fetal monitoring showed comparable reliability and sensitivity for monitoring fetal heart rate, but the agreement between the two devices was poor for uterine contraction frequency and intensity, while offering a better user experience for both patients and healthcare providers.