A new algorithm for fetal heart rate detection: Fractional order calculus approach

•Modified Pan-Tompkins’ algorithm (mPT) with fractional order derivative and moving average filter shows promising results.•mPT reaches satisfactory results for fetal QRS detection (F1 score of 97%).•Optimal order of fractional order derivative for fetal QRS detection is 0.51.•Optimal window width of MA filter for fetal QRS detection is 24.5 ms.•Extravagance of fetal QRS peaks compared to its surroundings is a promising estimate of fetal ECG quality. A new modified Pan-Tompkins’ (mPT) method for fetal heart rate detection is presented. The mPT method is based on the hypothesis that optimal fractional order derivative and optimal window width of the moving average filter would enable efficient estimation of fetal heart rate from surface abdominal electrophysiological recordings with relatively low signal-to-noise ratios. The algorithm is tested on signals recorded from the abdomen of pregnant women available from the PhysioNet Computing in Cardiology Challenge database. Fetal heart rate detection is performed on 10-s long segments selected by the estimation of signal-to-noise ratios (the extravagance of the fetal QRS peak to its surroundings and to the whole signal; and the mean ratio of fetal and maternal QRS peaks) and on the manually selected segments. The best results are obtained via criteria based on the extravagance of the fetal QRS peak to its surroundings that reached average sensitivity of 97%, positive predictive value of 97%, error rate of ∼3.5%, and F1 score of 97%. The obtained averaged optimal parameters for mPT are 0.51 for fractional order and 24.5 ms for the window width of the moving average filter. Proposed mPT algorithm showed satisfactory performance for fetal heart rate detection. Further adaptations of the presented mPT method could be used for peak detection in noisy environments in biomedical signal analysis in general.