title: Distribution of fetal erythroblasts in maternal blood after chorionic villous sampling.
abstract: OBJECTIVE
  To investigate whether chorionic villus sampling (CVS) is associated with an increase in fetomaternal cell trafficking.
  
  
  METHODS
  Prospective study.
  
  
  METHODS
  King's College London School of Medicine, King's College Hospital.
  
  
  METHODS
  Eighteen singleton pregnancies undergoing CVS for fetal karyotyping at 11-14 weeks of gestation and subsequently found to have chromosomal defects.
  
  
  METHODS
  Maternal blood samples were obtained immediately before and at 3-14 (median 5) days after CVS. Fetal erythroblasts were isolated using triple density gradient separation and anti-CD71 magnetic cell sorting techniques. The enriched erythroblasts were stained with Kleihauer-Giemsa and with fluorescent antibodies for the epsilon (epsilon) and gamma (gamma) globin chains. The percentage of fetal cells positive for each stain was calculated. Fluorescence in situ hybridisation (FISH) for X- and Y-chromosomes was also performed. Comparison was made in the proportion of enriched fetal cells between the pre-CVS and post-CVS samples.
  
  
  METHODS
  The proportion of fetal erythroblasts in maternal blood.
  
  
  RESULTS
  The percentage of erythroblasts enriched from maternal blood that stained positive for epsilon and gamma globin chains and with Kleihauer-Giemsa was significantly higher in the post-CVS samples compared with the pre-CVS samples. FISH analysis for the Y-chromosome confirmed the increase in fetal cell proportion in the post-CVS samples. The percentage difference in fetal cells decreased significantly with time interval from CVS.
  
  
  CONCLUSIONS
  CVS results in an increase in fetomaternal cell trafficking, which continues to be present for several days after the procedure.
authors.affiliation: Harris Birthright Research Centre for Fetal Medicine, King's College London School of Medicine, King's College Hospital, Denmark Hill, London, UK.
authors.forename: Raghad
authors.initials: R
authors.lastname: Al-Mufti
authors.forename: Henry
authors.initials: H
authors.lastname: Hambley
authors.forename: Farzin
authors.initials: F
authors.lastname: Farzaneh
authors.forename: Kypros H
authors.initials: KH
authors.lastname: Nicolaides
mesh_terms: D000328:Adult; D002469:Cell Separation / Q000379:methods; D015193:Chorionic Villi Sampling / Q000009:adverse effects*; D004900:Erythroblasts / Q000166:cytology*; D005260:Female; D005331:Fetomaternal Transfusion / Q000097:blood* / Q000209:etiology; D006801:Humans; D007150:Immunohistochemistry / Q000379:methods; D017404:In Situ Hybridization, Fluorescence; D011247:Pregnancy; D011250:Pregnancy Complications, Hematologic / Q000097:blood* / Q000209:etiology; D011446:Prospective Studies