Fetal Heart Rate Classification Proposed by the Perinatology Committee of the Japan Society of Obstetrics and Gynecology: Reproducibility and Clinical Usefulness

Aim: Intrapartum management guidelines based on fetal heart rate classification comprising a 5-tier system (Levels 1-5) was proposed by the Perinatology Committee of the Japan Society of Obstetrics and Gynecology (JSOG). This study aimed to assess the reproducibility and clinical usefulness of this classification. Methods: For assessing intraobserver and interobserver reproducibility in the interpretation of fetal heart rate tracing, 2 obstetricians reviewed 247 fetal heart rate tracings using the JSOG classification (Level 1, normal; Level 2, benign variant; Level 3, mild variant; Level 4, moderate variant; and Level 5, severe variant) and a subjective 3-tier classification (normal, equivocal, and ominous). In a separate series, we investigated whether the JSOG classification is related to early neonatal outcome and the delivery mode in 96 deliveries. Results: Weighted kappa coefficients of intraobserver and interobserver reproducibility in the interpretation of fetal heart rate tracings based on the JSOG classification were 0.73 to 0.77 and 0.70, respectively. In the subjective classification, these values were 0.69 to 0.72 and 0.59. There was a progressive increase in the rate of instrumental or cesarean deliveries across the 5 levels of the JSOG classification (P