title: Umbilical cord nucleated red blood cell counts: normal values and the effect of labor.
abstract: OBJECTIVE
  To determine the umbilical cord blood nucleated red blood cell (UC-nRBC) count in uncomplicated pregnancies delivered by elective cesarean section or delivered vaginally.
  
  
  METHODS
  A total of 57-term singleton pregnancies were studied: 33 with elective cesarean sections and 24 with vaginal deliveries. UC-nRBC was analyzed for its nucleated red blood cell counts. A logarithmic transformation of the data was used for statistical analysis.
  
  
  RESULTS
  The mean+/-standard deviation (s.d.) for nucleated red blood cell per 100 white blood cells (nRBC/100WBC) from the elective cesarean section group was 7.8+/-7.4. The vaginal delivery group had a mean value of 9.3+/-10.5, which was not significantly different. A value of 22 nRBC/100WBC defined the upper 95% confidence limit. The correlation between absolute nRBC and nRBC/100 WBC was 0.97.
  
  
  CONCLUSIONS
  Although chronic hypoxia is associated with elevated nRBC, the stress of uncomplicated labor does not change the level. This adds credence to its use as a marker for hypoxia preceding labor and delivery.
authors.affiliation: Department of Obstetrics and Gynecology of the University of South Florida College of Medicine, Tampa, FL 33606, USA. jmccarth@hsc.usf.edu
authors.forename: J M
authors.initials: JM
authors.lastname: McCarthy
authors.forename: T
authors.initials: T
authors.lastname: Capullari
authors.forename: Z
authors.initials: Z
authors.lastname: Thompson
authors.forename: Y
authors.initials: Y
authors.lastname: Zhu
authors.forename: W N
authors.initials: WN
authors.lastname: Spellacy
mesh_terms: D000328:Adult; D015415:Biomarkers / Q000097:blood; D016022:Case-Control Studies; D002585:Cesarean Section / Q000009:adverse effects / Q000379:methods; D036861:Delivery, Obstetric / Q000009:adverse effects / Q000379:methods*; D004900:Erythroblasts / Q000166:cytology*; D004906:Erythrocyte Count; D005260:Female; D005312:Fetal Blood / Q000166:cytology*; D047109:Fetal Development; D005311:Fetal Hypoxia / Q000097:blood / Q000175:diagnosis*; D005865:Gestational Age; D006801:Humans; D008423:Maternal Age; D010298:Parity; D011237:Predictive Value of Tests; D011247:Pregnancy; D011256:Pregnancy Outcome; D011379:Prognosis; D012016:Reference Values; D012680:Sensitivity and Specificity
chemical_list: D015415:Biomarkers