title: The value of repeated evaluation after initial failed nuchal translucency measurement.
abstract: OBJECTIVE
  The purpose of this study was to assess the value of reattempting the nuchal translucency (NT) measurement after an initial failure.
  
  
  METHODS
  Women undergoing NT measurements by NT-certified sonographers within a combined screening program over an 18-month period were categorized as "desiring" screening (all women), "eligible" (live fetus with crown-rump length of 45-84 mm), and "defaulters" (failed to keep a visit after a failed NT measurement attempt). If the NT measurement was unobtainable, patients with live fetuses and a crown-rump length of less than 84 mm were offered reexamination.
  
  
  RESULTS
  Nuchal translucency measurement success rates at the initial visit for those desiring (n = 837) and eligible (n = 767) were 73.3% and 80.0%, respectively. Composite NT measurement success rates for up to 3 visits were significantly greater than for only 1 visit for those desiring screening (84.8%; P < .0001), eligible for screening (86.6%; P = .0004), and not defaulting on follow-up (97.0%; P < .0001). The screen-positive rates were similar for 1 and up to 3 visits (10.4% and 11.0%). One additional (16.6%) aneuploidy was detected through a second visit.
  
  
  CONCLUSIONS
  Reattempting NT measurements significantly increases the overall NT measurement success rate and detects additional aneuploidies at constant screen-positive and invasive prenatal diagnosis rates.
authors.affiliation: Division of Maternal-Fetal Medicine, Department of Obstetrics and Gynecology, Maine Medical Center, Portland, Maine 04102 USA. waxj@mmc.org
authors.forename: Joseph R
authors.initials: JR
authors.lastname: Wax
authors.forename: Michael G
authors.initials: MG
authors.lastname: Pinette
authors.forename: Angelina
authors.initials: A
authors.lastname: Cartin
authors.forename: Jacquelyn
authors.initials: J
authors.lastname: Blackstone
mesh_terms: D025063:Chromosome Disorders / Q000000981:diagnostic imaging*; D005260:Female; D006801:Humans; D048208:Nuchal Translucency Measurement / Q000379:methods*; D011247:Pregnancy; D011785:Quality Assurance, Health Care / Q000379:methods*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity