title: A risk stratification model to predict adverse neonatal outcome in labor.
abstract: OBJECTIVE
  The development and evaluation of a labor risk model consisting of a combination of antepartum risk factors and intrapartum fetal heart rate (FHR) characteristics that can reliably identify those infants at risk for adverse neonatal outcome in labor.
  
  
  METHODS
  A nested case-control study of term singleton deliveries at the nine hospitals between March 2007 and December 2009. Eligibility criteria included: gestational age ≥ 37.0 weeks; singleton pregnancy; documented continuous FHR monitoring for ≥ 2 h before delivery; assessment of FHR tracing at least every 20 min; and, available maternal and neonatal outcomes. Adverse neonatal outcome was defined as nonanomalous infants admitted to the newborn intensive care unit with either a 5 minute Apgar score <7 or an umbilical artery pH<7.1. Initial risk score was determined using data available at 1 h after admission. Patients with an initial risk score between 7 and 15 were considered high risk. Intrapartum risk scores were then created for these patients using FHR tracing data and labor characteristics.
  
  
  RESULTS
  A total of 51 244 patients were identified meeting study criteria. Of the antepartum variables evaluated (n=31), 10 were associated with an adverse outcome. The high-risk group made up 28% of the population and accounted for 59.8% of the adverse outcomes. Intrapartum characteristics were then evaluated in this high-risk group. Intrapartum evaluation identified the highest risk group with a C/S rate of 40% and adverse outcome rate of 11.3%.
  
  
  CONCLUSIONS
  Incorporation of maternal and antepartum risk factors with FHR analysis can improve the ability to identify the fetus at risk in labor.
authors.affiliation: 1] Department of Maternal-Fetal Medicine, Intermountain Healthcare, Salt Lake City, UT, USA [2] Department of Obstetrics and Gynecology, University of Utah School of Medicine, Salt Lake City, UT, USA.
authors.forename: C M
authors.initials: CM
authors.lastname: Holmgren
authors.forename: M S
authors.initials: MS
authors.lastname: Esplin
authors.forename: M
authors.initials: M
authors.lastname: Jackson
authors.forename: T F
authors.initials: TF
authors.lastname: Porter
authors.forename: E
authors.initials: E
authors.lastname: Henry
authors.forename: B D
authors.initials: BD
authors.lastname: Horne
authors.forename: M W
authors.initials: MW
authors.lastname: Varner
mesh_terms: D000328:Adult; D000465:Algorithms; D015148:Cardiotocography; D016022:Case-Control Studies; D005260:Female; D006340:Heart Rate, Fetal; D006801:Humans; D007231:Infant, Newborn; D007743:Labor, Obstetric; D008423:Maternal Age; D011247:Pregnancy; D011248:Pregnancy Complications; D011256:Pregnancy Outcome; D011379:Prognosis; D018570:Risk Assessment / Q000379:methods*; D012307:Risk Factors