title: A comparison of episodic heart-rate patterns in the fetus and newborn.
abstract: Fourier analysis was applied to episodes of high and low heart-rate variation in the near-term fetus. The spectral densities of the variations in pulse intervals from 1 to 7 cycles/min, were almost identical with those found by De Haan et al. (1977) in the newborn infant during both active and quiet sleep. A computer programme, designed to separate low and high heart-rate variation episodes in the fetus, identified seven of the eight quiet sleep episodes in four infants. None of the other neonatal behavioural states had low heart-rate variation. It was concluded that, with other published data, there is increasing, although indirect, evidence that low heart-rate variation episodes indicate quiet sleep in the human fetus near term.
mesh_terms: D004562:Electrocardiography; D005260:Female; D005318:Fetal Heart / Q000502:physiology*; D005583:Fourier Analysis; D006339:Heart Rate; D006801:Humans; D007231:Infant, Newborn; D011247:Pregnancy; D012890:Sleep / Q000502:physiology