Rejection of the maternal electrocardiogram in the electrohysterogram signal

The electrohysterogram (EHG) signal is mainly corrupted by the mother's ele ctrocardiogram (ECG), which remains present despite analog filtering during acquisition. Wavelets are a powerful denoising tool and have already prove d their efficiency on the EHG, In this paper, we propose a new method that employs the redundant wavelet packet transform. We first study wavelet pack et coefficient histograms and propose an algorithm to automatically detect the histogram mode number. Using a new criterion, we compute a best basis a dapted to the denoising, After EHG wavelet packet coefficient thresholding in the selected basis, the inverse transform is applied. The ECG seems to b e very efficiently removed.