Electronic fetal monitoring then and now.
Chez
B F
BF
D001145:Arrhythmias, Cardiac / Q000145:classification / Q000266:history; D004582:Electronics, Medical / Q000266:history; D005260:Female; D005323:Fetal Monitoring / Q000266:history*; D006340:Heart Rate, Fetal; D049673:History, 20th Century; D006801:Humans; D011247:Pregnancy