title: Fetal heart rate changes and cerebral oxygenation measured by near-infrared spectroscopy during the first stage of labour.
abstract: OBJECTIVE
  To determine the relationship between contraction related changes in fetal heart rate and cerebral oxygenation measured by near-infrared spectroscopy during labour.
  
  
  METHODS
  A specially designed optical probe was inserted through the dilated cervix and placed against the fetal head in 30 women during labour. Alterations in fetal heart rate during the final hour of the first stage of labour were compared with changes in the cerebral haemoglobin oxygenation index (delta oxyhaemoglobin concentration - delta deoxyhaemoglobin concentration) measured before, during and after uterine contractions.
  
  
  RESULTS
  Uterine contractions which were associated with either no alteration, accelerations or early decelerations of the fetal heart rate showed no significant changes in the haemoglobin oxygenation index. Variable, late and prolonged decelerations all showed significant decreases in the haemoglobin oxygenation index (P < 0.01) either during (variable) or after (variable, late and prolonged) the uterine contraction.
  
  
  CONCLUSIONS
  The association between variable, late and prolonged FHR decelerations and significant falls in cerebral oxygenation during late labour suggests that these fetal heart rate patterns are associated with an increased risk of fetal cerebral hypoxia.
authors.affiliation: Departments of Obstetrics and Gynaecology, University College London Medical School, UK.
authors.forename: C J
authors.initials: CJ
authors.lastname: Aldrich
authors.forename: D
authors.initials: D
authors.lastname: D'Antona
authors.forename: J A
authors.initials: JA
authors.lastname: Spencer
authors.forename: D T
authors.initials: DT
authors.lastname: Delpy
authors.forename: E O
authors.initials: EO
authors.lastname: Reynolds
authors.forename: J S
authors.initials: JS
authors.lastname: Wyatt
mesh_terms: D000328:Adult; D001921:Brain / Q000378:metabolism*; D005260:Female; D006340:Heart Rate, Fetal; D006801:Humans; D007747:Labor Stage, First; D010108:Oxyhemoglobins / Q000378:metabolism*; D011247:Pregnancy; D013055:Spectrophotometry, Infrared
chemical_list: D010108:Oxyhemoglobins