Experience with an ultrasonic foetal pulse detector.
D000022:Abortion, Spontaneous / Q000175:diagnosis; D000328:Adult; D002585:Cesarean Section; D005260:Female; D005318:Fetal Heart / Q000502:physiology*; D006801:Humans; D010920:Placenta; D011247:Pregnancy; D014465:Ultrasonics / Q000295:instrumentation; D014463:Ultrasonography