Is fetal heart rate variability a good predictor of fetal outcome?
OBJECTIVE: The purpose of this study was to investigate, in a prospective manner, whether fetal heart rate (FHR) variability serves as a reliable single predictor of fetal outcome. METHODS: We undertook a prospective study of 2,200 consecutive deliveries. Preterms < 37 weeks, twins, stillbirths and fetal malformations were excluded from the study. FHR tracings were analyzed for variability in every delivery. Three windows were evaluated: 1) early in labor (30 min); 2) in the active phase of labor - 1 h prior to complete cervical dilatation (30 min); and 3) throughout the second stage of delivery, in segments of 30 min. Using the tracings taken at admission and prior to delivery, FHR variability was scored according to five previously used evaluative methods, and was correlated to the following three fetal outcome parameters: a) arterial cord blood pH < 7.2, > 7.2; b) 5-min Apgar >6, < 7; and c) immediate outcome ('good' defined as newborn going home after 2-5 days, with no neonatal int
