title: Intrapartum fetal heart rate patterns preceding terminal bradycardia in infants (>34 weeks) with poor neurological outcome: A regional population-based study in Japan.
abstract: OBJECTIVE
  Intrapartum fetal bradycardia necessitates immediate operative delivery. Our aim was to investigate the hypothesis that some non-reassuring fetal heart rate (FHR) patterns were present before the onset of terminal bradycardia in infants who developed subsequent brain damage.
  
  
  METHODS
  From a population-based study of 65,197 deliveries, 190 stillbirths, 115 neonatal deaths, and 136 neurologically high-risk infants were registered by the Miyazaki Perinatal Conference. There were 15 cases of neurologically high-risk infants born at >34 weeks of gestation exhibiting intrapartum terminal bradycardia. Focusing on the brain-damaged infants, we retrospectively analyzed FHR patterns for at least 1 h prior to the bradycardia.
  
  
  RESULTS
  Brain damage (cerebral palsy [n = 11] and mental retardation [n = 2]) was diagnosed at 2 years old in 13 out of 15 neurologically high-risk infants. Two infants had bradycardia on admission. In the remaining 11 infants, FHR patterns were reassuring in six (55%) and non-reassuring in five (45%), including late decelerations (n = 4) and variable decelerations (n = 2). Clinically relevant factors in the non-reassuring group included intrauterine infection (n = 3), malpresentation with umbilical cord coiling (n = 1), and unknown causes (n = 1). Clinically relevant features in the reassuring group included cord prolapse (n = 1), vaginal breech delivery (n = 1), shoulder dystocia (n = 1), rupture of membranes (n = 1), and unknown causes (n = 2).
  
  
  CONCLUSIONS
  More than half of the brain-damaged infants born at >34 weeks of gestation who exhibited intrapartum terminal bradycardia had unremarkable FHR patterns before abrupt-onset bradycardia. For those with non-reassuring patterns preceding bradycardia, intrauterine infection was the major sentinel event.
authors.affiliation: Department of Obstetrics and Gynecology and Perinatal Center, Faculty of Medicine, University of Miyazaki, Miyazaki, Japan.
authors.forename: Yuki
authors.initials: Y
authors.lastname: Kodama
authors.affiliation: Department of Obstetrics and Gynecology and Perinatal Center, Faculty of Medicine, University of Miyazaki, Miyazaki, Japan.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Sameshima
authors.affiliation: Department of Obstetrics and Gynecology and Perinatal Center, Faculty of Medicine, University of Miyazaki, Miyazaki, Japan.
authors.forename: Rie
authors.initials: R
authors.lastname: Yamashita
authors.affiliation: Department of Obstetrics and Gynecology and Perinatal Center, Faculty of Medicine, University of Miyazaki, Miyazaki, Japan.
authors.forename: Masanao
authors.initials: M
authors.lastname: Oohashi
authors.affiliation: Department of Obstetrics and Gynecology and Perinatal Center, Faculty of Medicine, University of Miyazaki, Miyazaki, Japan.
authors.forename: Tsuyomu
authors.initials: T
authors.lastname: Ikenoue
mesh_terms: D000328:Adult; D001919:Bradycardia / Q000150:complications / Q000175:diagnosis*; D001927:Brain Diseases / Q000209:etiology*; D005260:Female; D005313:Fetal Death; D005315:Fetal Diseases / Q000175:diagnosis*; D005323:Fetal Monitoring; D006340:Heart Rate, Fetal; D006801:Humans; D008607:Intellectual Disability / Q000209:etiology*; D007564:Japan; D011247:Pregnancy; D050497:Stillbirth
keywords: cerebral palsy; fetal bradycardia; fetal heart rate monitoring; intrauterine infection; non-reassuring patterns