The association between cardiac accelerations and movements in fetal sheep.

Observations in 5 fetal sheep at 120-134 days gestation, using either real time ultrasound or direct emg recordings to detect fetal movements, showed an association between such movements and cardiac accelerations (greater than 2 s duration and 4 beats/min amplitude). Neuromuscular blockade with gallamine abolished the fetal movements but not the accelerations.