Reliability and quality of ultrasound measurements of fetal heart rate variability

This work was aimed at assessment of usability of Doppler ultrasound method for the analysis of fetal heart rate variability at a level of single heart beats. The purpose of this study was to check if today fetal monitors provide the signal of accuracy comparable with an electrocardiography method. The virtual instrumentation software for measurement system and processing of acquired signals was implemented using LABVIEW environment. The results obtained reveal that accuracy of today monitors which use Doppler ultrasound technique is sufficient for visual analysis of the FHR traces. However, for the computerized analysis at a beat-to-beat level, this accuracy is below the acceptable value.