title: [Value of nasal bone and serological screening for the detection of fetal chromosomal disorders in second trimester].
abstract: OBJECTIVE
  To assess the value of fetal chromosomal abnormality screening by a maternal serum test plus fetal nasal bone length in second trimester (parallel test).
  
  
  METHODS
  From January 2009 to December 2010, fetal nasal bone was measured at 19 - 22 weeks gestation in 6173 unselected cases. Karyotyping was performed in cases with a high risk for maternal serum test and/or abnormal fetal nasal bone length. All cases were followed-up postnatally.
  
  
  RESULTS
  Nasal bone was assessed successfully in 5607 cases (90.83%). Normally it is increases with gestational age. The detection rate of chromosomal abnormality was 69.64% by maternal serum test, 79.76% by maternal serum test plus hypoplastic nasal bone and 83.93% by maternal serum test plus shortened nasal bone.
  
  
  CONCLUSIONS
  Fetal nasal bone hypoplasia is closely correlated with chromosomal abnormality. And sonographic evaluation of nasal bone may be a useful tool for screening chromosomal abnormality. The combination of maternal serum test and fetal nasal bone length will boost the detection rate of chromosomal abnormality.
authors.affiliation: Department of Ultrasound, Women & Children Hospital, Jiaxing 314000, China.
authors.forename: Chuan-yi
authors.initials: CY
authors.lastname: Xu
authors.forename: Xia
authors.initials: X
authors.lastname: Liu
authors.forename: Xiao-ying
authors.initials: XY
authors.lastname: Jin
mesh_terms: D025063:Chromosome Disorders / Q000097:blood* / Q000000981:diagnostic imaging*; D005260:Female; D006801:Humans; D009295:Nasal Bone / Q000000981:diagnostic imaging*; D011247:Pregnancy; D011262:Pregnancy Trimester, Second; D012698:Serologic Tests; D016216:Ultrasonography, Prenatal