title: More chorionic villi obtained at a single center compared to previously published reports.
abstract: Abstract Objective: The chorionic villus sampling (CVS) technique is not standardized between institutions and can vary greatly between operators. Our goal was to (1) compare the amount of villi obtained by the transabdominal (TA) and transcervical (TC) CVS; (2) compare our single center yield of villi to previously published reports.
  
  
  METHODS
  Women undergoing CVS in a singleton pregnancy between 2009 and 2011 were retrospectively identified at a single center. TA CVS was performed using a 20 gauge spinal needle. TC CVS was performed using a 1.4-mm suction catheter. Milligrams of villi and blood from all TA (n=97) and TC (n=36) CVS were obtained. STATA software was used to perform statistical analysis.
  
  
  RESULTS
  The median amount of tissue obtained during a TC CVS [50 mg ; range (5-200 mg)] was higher than the median amount obtained from TA CVS [36 mg; range (8-140 mg)]; p=0.002. There was more blood contamination in the samples obtained using the TC approach (median=10 mg; range 5-40 mg) than in the samples from the TA approach (median=5 mg; range 0-27 mg); p<0.0001. The amount of villi obtained from our institution was significantly higher than has been previously reported [TC (p=0.0001) and TA (p<0.0001)].
  
  
  CONCLUSIONS
  TC CVS produced significantly more villi than the TA approach. However, both techniques generated enough villi for direct testing. This information may be useful when multiple genetic tests are being requested. Regardless of route of sampling, the volume of villi obtained was higher at our institution than previously reported. More information regarding amount of villi obtained and relationship to pregnancy complications is needed.
authors.affiliation: UNC Chapel Hill, Chapel Hill , NC , USA .
authors.forename: Neeta
authors.initials: N
authors.lastname: Vora
authors.forename: Emily
authors.initials: E
authors.lastname: Hardisty
authors.forename: Atena
authors.initials: A
authors.lastname: Asiaii
authors.forename: Adam
authors.initials: A
authors.lastname: Wolfberg
authors.forename: Antoni
authors.initials: A
authors.lastname: Borrell
mesh_terms: D015193:Chorionic Villi Sampling / Q000379:methods* / Q000706:statistics & numerical data; D005260:Female; D006801:Humans; D011247:Pregnancy; D012189:Retrospective Studies
keywords: Chorionic villus sampling; prenatal diagnosis; transabdominal; transcervical