The evolution of continuous electronic fetal heart rate (FHR) monitoring has presented the obstetrician with a critical clinical conundrum: basic science observations suggested that such monitoring may be associated with improved long-term neurologic outcomes, but evidence for such improvement remains lacking after a half-century of use and millions of cesarean deliveries based on FHR monitoring. Electronic fetal heart rate (FHR) monitoring was initially designed to prevent sudden intrapartum fetal death. As a result, this technology has proven extremely effective—intrapartum stillbirth in a monitored fetus is almost never encountered today.
The contradiction appeared to be connected to common misunderstandings about the physiology behind diverse FHR patterns and the developmental origins of cerebral palsy. The misconceptions were exacerbated by the reliance on anecdotal experience and tradition over evidence-based medicine, the perplexing “category II” FHR designation, medical-legal considerations, and the tendency to view fetal monitoring as a single, indivisible entity whose concepts must be accepted or rejected as a whole. As a result, ill-defined and fictitious illnesses, such as “fetal reserve depletion,” are especially dangerous because their use in clinical treatment is based on no evidence. A coordinated effort, including instructors, authors, and researchers, would be required to address this self-inflicted harm to the specialty.