title: "Does short-term variation in fetal heart rate predict fetal acidaemia?" A systematic review and meta-analysis.
abstract: OBJECTIVE
  To evaluate the association of short-term variation (STV) of the fetal heart rate in predicting fetal acidaemia at birth.
  
  
  METHODS
  The search strategy employed searching of electronic databases (MEDLINE, Web of Science, Scopus, and Google Scholar) and reference lists of relevant studies. Data were extracted from studies, adhering strictly to the following criteria: singleton pregnancy at ≥24 weeks' gestation, computerized CTG (index test) and calculation of STV before delivery. The outcome measure was arterial pH assessed in cord blood obtained at birth.
  
  
  RESULTS
  Meta-analysis showed moderate accuracy of STV in predicting fetal acidaemia with a sensitivity of 0.57 (95% CI: 0.45-0.68), specificity of 0.81 (95% CI: 0.69-0.89), positive likelihood ratio of 3.14 (95% CI: 2.13-4.63) and negative likelihood ratio of 0.58, (95% CI: 0.46-0.72). However, in intra-uterine growth restricted fetuses, a small improvement in detecting acidaemia was observed; with a sensitivity of 0.63 (95% CI: 0.49-0.75) and negative likelihood ratio of 0.50 (95% CI: 0.31-0.80).
  
  
  CONCLUSIONS
  STV appears to be a moderate predictor for fetal acidaemia. However, its usefulness as a stand-alone test in predicting acidaemia in clinical setting remains to be determined.
authors.affiliation: a Department of Human Metabolism , Academic Unit of Reproductive & Developmental Medicine , Sheffield , UK .
authors.forename: Habiba
authors.initials: H
authors.lastname: Kapaya
authors.affiliation: b School of Health and Related Research (ScHARR), University of Sheffield , Sheffield , UK.
authors.forename: Richard
authors.initials: R
authors.lastname: Jacques
authors.affiliation: a Department of Human Metabolism , Academic Unit of Reproductive & Developmental Medicine , Sheffield , UK .
authors.forename: Nadia
authors.initials: N
authors.lastname: Rahaim
authors.affiliation: a Department of Human Metabolism , Academic Unit of Reproductive & Developmental Medicine , Sheffield , UK .
authors.forename: Dilly
authors.initials: D
authors.lastname: Anumba
mesh_terms: D000138:Acidosis / Q000175:diagnosis*; D015148:Cardiotocography; D005260:Female; D005865:Gestational Age; D006340:Heart Rate, Fetal / Q000502:physiology*; D006801:Humans; D007231:Infant, Newborn; D011247:Pregnancy; D011296:Prenatal Diagnosis; D012372:ROC Curve; D012015:Reference Standards; D012306:Risk; D012680:Sensitivity and Specificity
keywords: Computer analysis; computerized cardiotocography; fetal acidaemia; fetal acid–base status; fetal heart rate; neonatal acidaemia; short-term variation; umbilical blood gas analysis