This article has been accepted for publication in a future issue of this journal, but has not been fully edited. Content may change prior to final publication. TITB-00018-2006.R2

Abstract—This paper introduces an automated methodology for the extraction of fetal heart rate from cutaneous potential abdominal ECG recordings. A three-stage methodology is proposed. Having the initial recording, which consists of a small number of abdominal ECG leads, in the first stage the maternal R-peaks and fiducial points (QRS onset and offset) are detected, using time-frequency analysis and medical knowledge. Then, the maternal QRS complexes are eliminated. In the second stage the positions of the candidate fetal R-peaks are located using complex wavelets and matching theory techniques. In the third stage, the fetal R-peaks which overlap with the maternal QRS complexes (eliminated in the first stage) are found using two approaches: a heuristic algorithm and a histogram-based technique. The fetal R-peaks detected, are used to calculate the fetal heart rate. The methodology is validated using a dataset of 8 short and 10 long duration recordings, obtained between the 20th and the 41st week of gestation and the obtained accuracy is 97.47%. The proposed methodology is advantageous since it is based on the analysis of few abdominal leads, in contrast to other proposed methods which need a large number of leads. Index Terms—Abdominal ECG, fetal ECG, fetal heart rate, time-frequency analysis