Fetal heart rate extraction from composite maternal ECG using complex continuous wavelet transform

Fetal heart rate extraction from the abdominal ECG is of great importance due to the information that carries in assessing appropriately the fetus well-being during pregnancy. In this work a novel automated method is presented for the detection of the QRS complexes of the fetus cardiac activity using multichannel maternal ECG recordings. No accessory preprocessing step for noise filtering is required. The method is based on the complex continuous wavelet transform and modulus maxima theory. The proposed method was validated using real signals, recorded at different weeks of gestation, covering most of the pregnancy period. The system performs well, since almost all fetal beats are detected (accuracy: 99.5%).