Non-Invasive Fetal ECG Standardization: Assessing the Influence of Electrode Configurations and Fetal Position

Congenital heart defects (CHD) account for more than 1% of all newborns. An early detection of CHD results in a significant decrease of the mortality rate and long-term morbidity. Non-invasive fetal ECG (NI-fECG) is a promising option for complementing and potentially improving the early detection of congenital heart defects. To compare different morphologies, the fetal ECG needs to be standardized regarding the fetal position. Further, the influence of different electrode configurations on fetal ECG standardization is unknown. In this study, we evaluated six common electrode configurations in wearable devices and six fetal positions regarding their influence on the signal quality of the standardized 12-lead ECG. Therefore, we applied a state-of-the-art fetal ECG standardization algorithm by Lempersz et al. on the public noninvasive multimodal foetal ECG-Doppler dataset for antenatal cardiology research. We show that fetal ECG standardization is suited for various electrode configurations, although signal quality decreases with a reduced number of electrodes. Further, the fetal position has a clear impact on signal quality after standardization. This study improves the understanding of fetal ECG standardization and highlights the potential of NI-fECG as a tool to support prenatal CHD detection. Future work should focus on increasing the robustness of standardization for different fetal positions and should expand the analysis with recordings from fetuses with CHD to deepen understanding of differences in morphology.Clinical relevance- Non-invasive fetal ECG (NI-fECG) has the potential to improve prenatal detection rates of congenital heart defects. This study takes a step toward that goal by addressing signal quality variations caused by fetal position and electrode configuration in the standardization of fetal ECGs.