title: Fine-needle aspiration in the evaluation of nucleated red blood cells in the human placenta.
abstract: OBJECTIVE
  The purpose of this study was to evaluate the correlation between placental and umbilical cord nucleated red blood cell counts.
  
  
  METHODS
  Eighty placentas and their matched umbilical cord blood samples were collected prospectively immediately after delivery. In vitro fine-needle aspiration biopsy specimens were used to obtain placental tissue samples. Nucleated red blood cells were counted by both manual microscopy and flow cytometry. Statistical analysis included Wilcoxon signed rank test and Spearman correlation.
  
  
  RESULTS
  The median nucleated red blood cell counts/100 white blood cell counts for manual microscopy in umbilical cord blood; placental samples were 7.5 and 3.0, respectively (P <.0001). The median nucleated red blood cell counts for flow cytometric determination in umbilical cord blood and placental samples were 11.3 and 8.6, respectively (P <.0001). The Spearman correlation between manually counted umbilical cord blood samples and the placental tissue specimens was 0.66 (P <.0001). The Spearman correlation between flow cytometrically counted umbilical cord blood nucleated red blood cell and nucleated red blood cell counts that were obtained from the placenta was statistically significant (r = 0.74, P <.0001). The Spearman correlation between manual microscopy and flow cytometry for umbilical cord samples and their matched placental tissue specimens were 0.80 and 0.58, respectively, with all probability values at <.0001.
  
  
  CONCLUSIONS
  Previous studies have reported an association between acute and chronic hypoxia and elevated nucleated red blood cells. Our results indicate that in vitro placental nucleated red blood cell counts correlate with umbilical cord nucleated red blood cell counts and suggest that antenatal evaluation of fetal nucleated red blood cells could be achieved by placental fine-needle aspiration biopsy.
authors.affiliation: Departments of Obstetrics and Gynecology and Pathology, Lenox-Hill Hospital, New York, NY 10021, USA.
authors.forename: Didem
authors.initials: D
authors.lastname: Akyol
authors.forename: Christina
authors.initials: C
authors.lastname: Hajdu
authors.forename: Asaf
authors.initials: A
authors.lastname: Ferber
authors.forename: Christopher
authors.initials: C
authors.lastname: O'reilly-Green
authors.forename: Francesca R
authors.initials: FR
authors.lastname: Giancotti
authors.forename: Brent H
authors.initials: BH
authors.lastname: Dorsett
authors.forename: Elana
authors.initials: E
authors.lastname: Opher
authors.forename: Michael Y
authors.initials: MY
authors.lastname: Divon
mesh_terms: D000328:Adult; D001707:Biopsy, Needle; D004900:Erythroblasts / Q000166:cytology*; D004906:Erythrocyte Count; D005260:Female; D005312:Fetal Blood / Q000166:cytology; D005434:Flow Cytometry; D006801:Humans; D008853:Microscopy; D010920:Placenta / Q000166:cytology*; D011247:Pregnancy