The influence of signal loss on the comparison between computer analyses of the fetal heart rate in labour using pulsed doppler ultrasound (with autocorrelation) and simultaneous scalp electrocardiogram

Abstract A comparison between the computer analyses of records of the fetal heart rate (FHR) obtained simultaneously by pulsed doppler ultrasound with autocorrelation and by fetal scalp electrocardiogram (ECG) in labour showed no statistical differences when signal loss was less than 2%. Increasing signal loss, due to maternal movement, correlated significantly with greater differences between ultrasound and ECG values for mean FHR variation (r = 0.58, p