title: Increased risk of aneuploidy in women having unsuccessful chorionic villus sampling procedures.
abstract: OBJECTIVE
  To determine the incidence of fetal aneuploidy in women who had unsuccessful chorionic villus sampling (CVS) procedures.
  
  
  METHODS
  Retrospective study.
  
  
  METHODS
  Pennsylvania Hospital, Philadelphia, Pennsylvania, USA.
  
  
  METHODS
  Two thousand six hundred and sixty-eight women who underwent chorionic villus sampling, in 78 (2.9%) of whom villi could not be obtained.
  
  
  METHODS
  Sixty-nine of 78 (88%) women who had an unsuccessful CVS procedure underwent a subsequent amniocentesis later in the same pregnancy.
  
  
  METHODS
  The incidence of aneuploidy identified from amniotic fluid chromosome analysis in the 69 women who had an unsuccessful CVS procedure compared to the frequency of aneuploidy in women having a successful CVS procedure.
  
  
  RESULTS
  Of the 69 women who underwent a post-CVS amniocentesis because of failure to obtain chorionic villi, six aneuploid pregnancies were identified (8.7%). The frequency of aneuploidy in the 2590 successfully sampled CVS patients was 2.5%. This difference was statistically significant (P = 0.009) by Fisher's exact test (two-tailed).
  
  
  CONCLUSIONS
  Women having an unsuccessful CVS procedure should be informed that they may be at increased risk for carrying an aneuploid fetus.
authors.affiliation: Department of Obstetrics and Gynaecology, Pennsylvania Hospital, Philadelphia 19107.
authors.forename: A E
authors.initials: AE
authors.lastname: Donnenfeld
authors.forename: R J
authors.initials: RJ
authors.lastname: Librizzi
authors.forename: S
authors.initials: S
authors.lastname: Weiner
authors.forename: R J
authors.initials: RJ
authors.lastname: Bolognese
mesh_terms: D000649:Amniocentesis; D000782:Aneuploidy; D015193:Chorionic Villi Sampling / Q000009:adverse effects*; D005260:Female; D005315:Fetal Diseases / Q000175:diagnosis / Q000453:epidemiology / Q000209:etiology* / Q000235:genetics; D006801:Humans; D015994:Incidence; D010414:Pennsylvania / Q000453:epidemiology; D011247:Pregnancy; D011296:Prenatal Diagnosis; D012189:Retrospective Studies; D012307:Risk Factors