Current methods of continuous fetal heart rate monitoring.

The composite paper record of fetal heart rate (FHR) and uterine activity is known as a cardiotocograph (CTG). Interpretation of a CTG requires knowledge of the means by which the fetal heart beat signals are obtained. The continuous FHR record is derived from signals of consecutive fetal heart beats. Fetal hearts beats may be detected through the mother's abdomen by processing the Doppler shift of an ultrasound beam. The R waves of the fetal electrocardiogram (ECG) may be obtained by direct contact with the fetus through the cervix after rupture of the membranes.