title: A two-channel radiotelemetry system for clinical fetal monitoring.
abstract: A radiotelemetry system for monitoring fetal heart rate and uterine contractions during labor has been developed and evaluated. The two-channel transmitter utilizes a miniature intrauterine pressure sensor which frequency modulates a subcarrier. The fetal electrocardiogram picked up by a scalp electrode is summed with the subcarrier and this direct frequency modulates the RF carrier. The transmitter has been constructed in a miniature package using conventional electronic components. A receiver system which obtains the original signals and feeds them to a conventional fetal monitor has been developed for use with this transmitter. Clinical evaluation has shown the telemetry system to provide efficacious signals.
mesh_terms: D004562:Electrocardiography; D004581:Electronics / Q000295:instrumentation; D005260:Female; D005318:Fetal Heart / Q000502:physiology; D005323:Fetal Monitoring / Q000295:instrumentation / Q000379:methods*; D006339:Heart Rate; D006801:Humans; D011247:Pregnancy; D013686:Telemetry / Q000295:instrumentation / Q000379:methods*; D014160:Transducers, Pressure; D014590:Uterine Contraction