title: The quadruple test for Down syndrome screening in pregnant women of advanced maternal age.
abstract: OBJECTIVE
  The purpose of the current study was to determine whether or not the quadruple test for screening Down syndrome is an effective method to replace direct amniocentesis in pregnant women ≥ 35 years of age.
  
  
  METHODS
  This study analyzed the screening performance of the quadruple test according to maternal age at delivery among subjects who had a quadruple screening test at 1 of 4 hospitals during a 5-year period and for whom data on fetal chromosomal abnormalities were available.
  
  
  RESULTS
  The study population of 9,435 pregnant women was divided into 3 groups according to maternal age: 6,922 women were < 35 years of age; 2,284 were 35-39 years of age; and 229 women ≥ 40 years of age. The detection and false-positive rates of the quadruple screening test for Down or Edward syndrome in the 3 groups of women were 80 and 6.6%, 200 and 15.8%, and 100 and 35.3%, respectively.
  
  
  CONCLUSIONS
  Under conditions in which first trimester screening test is not available, the quadruple screening test is a better choice than direct amniocentesis for pregnancies complicated by advanced maternal age. When providing genetic counseling, we need to explain the accurate detection and false-positive rates of the screening test according to maternal age.
authors.affiliation: Department of Obstetrics and Gynecology, College of Medicine, Seoul St. Mary's Hospital, The Catholic University of Korea, #505 Banpodong, Sechogu, Seoul 137-040, Korea.
authors.forename: Ji Young
authors.initials: JY
authors.lastname: Kwon
authors.forename: In Yang
authors.initials: IY
authors.lastname: Park
authors.forename: Seong-Min
authors.initials: SM
authors.lastname: Kwon
authors.forename: Chan Joo
authors.initials: CJ
authors.lastname: Kim
authors.forename: Jong Chul
authors.initials: JC
authors.lastname: Shin
mesh_terms: D000328:Adult; D000649:Amniocentesis / Q000379:methods; D004314:Down Syndrome / Q000175:diagnosis*; D005189:False Positive Reactions; D005260:Female; D005820:Genetic Testing / Q000379:methods*; D006801:Humans; D008423:Maternal Age; D008875:Middle Aged; D011247:Pregnancy; D011261:Pregnancy Trimester, First; D011262:Pregnancy Trimester, Second; D011296:Prenatal Diagnosis / Q000379:methods*; D012680:Sensitivity and Specificity