title: Fetal nuchal translucency thickness in different cut-off points for aneuploidy screening in the south of Vietnam.
abstract: OBJECTIVE
  The purpose of this study was to define the most suitable cut-off point for fetal nuchal translucency thickness in a screening program for aneuploidy and trisomy 21 in the south of Vietnam.
  
  
  METHODS
  Two thousand and five hundred cases of singleton pregnancies were followed prospectively from the first trimester to the delivery. The rate of aneuploidy was calculated by seeking a relationship to increased fetal nuchal translucency thickness then calculating the sensitivity and specificity of different cut-off points in thickness measurement to find the most suitable point for screening.
  
  
  RESULTS
  The prevalence of fetal abnormality was 1.5% (95% CI 1.1-2.1), and 1.2% (95% CI 0.8-1.7) of aneuploidy cases found and the commonest was trisomy 21. A cut-off point at 2.4 mm showed the highest level of sensitivity and specificity for the detection of aneuploidy (65.5 and 95.7%) and trisomy 21 (75.0 and 95.1%), with a false-positive rate of 4.3 and 4.9%, respectively.
  
  
  CONCLUSIONS
  Using a cut-off point of nuchal translucency at 2.4 mm has potential for aneuploidy and trisomy 21 screening in the south of Vietnam.
authors.affiliation: Department of Obstetrics and Gynaecology, University of Medicine and Pharmacy, Ho Chi Minh City, Vietnam. tomaixuanhong@yahoo.com
authors.forename: Xuan-Hong
authors.initials: XH
authors.lastname: Tomai
authors.forename: Jean-Pierre
authors.initials: JP
authors.lastname: Schaaps
authors.forename: Jean-Michel
authors.initials: JM
authors.lastname: Foidart
mesh_terms: D000328:Adult; D000782:Aneuploidy; D004314:Down Syndrome / Q000175:diagnosis* / Q000000981:diagnostic imaging; D005260:Female; D006801:Humans; D048208:Nuchal Translucency Measurement / Q000379:methods*; D011247:Pregnancy; D012680:Sensitivity and Specificity; D016216:Ultrasonography, Prenatal; D014744:Vietnam