TECHNIQUES FOR OPTIMAL ENHANCEMENT AND FEATURE-EXTRACTION OF FETAL ELECTROCARDIOGRAM

Detailed analysis of the fetal electrocardiogram (EGG) during labour could provide valuable additional information to assist clinicians in reducing incidents of unnecessary medical intervention without altering current patient handling routines, but poor signal quality and difficulty of processing the ECG without significant distortion have impeded such analysis. The paper presents novel optimum curve fitting and digital filtering techniques that make it possible to enhance the quality of the ECG with minimal distortion and to measure, on a beat-by-beat basis, almost any feature (e.g. time constants, amplitudes, areas, maxima and minima) from the fetal ECG waveform accurately. This development removes a major obstacle in the use of fetal ECG and creates a basis for a thorough analysis of the changes in the key fetal ECG features and for evaluating their clinical value in fetal monitoring.