OverviewElectronic Fetal Heart Rate Monitoring: The 5-Tier System, Third Edition describes the common practices of fetal heart rate monitoring and interpretation in midwifery and nursing practice. It contains the most up-to-date evidence for clinical management of fetal heart rate monitoring during a woman's labor. The Third Edition outlines the basic physiology of the fetal heart and fetal circulation, acid-base balance, and fetal cerebral metabolism. In addition, it describes the fetal heart rate monitoring technology currently in use. Also reviewed are the nomenclature, definitions, and the underlying physiologic mechanisms for variant fetal heart rate patterns.