Intrapartum fetal heart rate monitoring. I. Classification and prognosis of fetal heart rate patterns
A total of 1,996 direct fetal heart rate (FHR) tracings in labor were analyzed using the first and last 30 minutes of monitoring in order to evaluate individual FHR characteristics as to their ability to predict the fetal status. Comparisons were made between individual FHR characteristics occurring alone ("uncomplicated") and those occurring in association with others ("complicated") in predicting fetal status as judges by 1 and 5 minute Apgar scores. These comparisons were made separately for the first 30 minutes and the last 30 minutes of monitoring.
Krebs, HB., Petres, RE., Dunn, LJ., Jordaan, HV., & Segreti, A. (1979). Intrapartum fetal heart rate monitoring. I. Classification and prognosis of fetal heart rate patterns. American Journal of Obstetrics and Gynecology, 133(7), 762-772.