Accuracy of predicting neonatal distress using a five-level classification of fetal heart rate monitoring

J Obstet Gynaecol Res. 2021 Jan;47(1):254-261. doi: 10.1111/jog.14490. Epub 2020 Sep 16.

Abstract

Aim: To assess the accuracy of neonatal distress prediction using the five-level classification of fetal heart rate (FHR) and management protocol of the Japan Society of Obstetrics and Gynecology (JSOG).

Methods: A case-control study was conducted. Vertex singleton pregnant women who delivered after 37 weeks' gestation from 2013 to 2015 were enrolled. The participants were categorized into two groups; controls were levels 1-3 (n = 1184), whereas cases were levels 4-5 (n = 117) group. Neonatal distress was defined as Apgar score < 8 points at 5 min or umbilical cord artery pH < 7.1.

Results: There were 117 cases (9.0%). The frequency of the neonatal distress was observed in 1.3% controls and 6.8% cases (P < 0.01). Diagnostic accuracy of neonatal distress for cases showed a 6.8% positive-predictive value, 34.8% sensitivity, 91.5% specificity and 98.7% negative-predictive value. Among various obstetrical conditions, high sensitivity (100%) for prediction of neonatal distress was observed in women with chromosome abnormalities, placental abruption, umbilical cord abnormalities and excessive labor pain. Conversely, relatively low specificity (<50%) was observed in cases with oligohydramnios and excessive labor pain.

Conclusion: The five-level classification scheme was efficient for neonatal distress prediction. However, depending on the obstetric condition, the FHR findings and neonatal condition might be independent.

Keywords: cardiotocogram; fetal heart rate monitoring; neonatal distress; nonreassuring fetal status.

MeSH terms

  • Apgar Score
  • Case-Control Studies
  • Female
  • Fetal Distress / diagnosis
  • Fetal Monitoring
  • Heart Rate, Fetal*
  • Humans
  • Infant, Newborn
  • Japan
  • Placenta*
  • Pregnancy