title: Down's syndrome: prospects for prevention by antenatal diagnosis.
abstract: The results of a prospective study on cytogenetic analysis of Chorionic Villus Samples (CVS) taken in early pregnancy (after 10 weeks) from pregnant ladies aged between 22 and 50 years are being presented.
  
  
  OBJECTIVE
  To find out the prevalence of chromosomal defects with advancing age of the mother.
  
  
  METHODS
  Department of Medical Genetics, Armed Forces Institute of Pathology, Rawalpindi.
  
  
  METHODS
  A total of 48 samples have been studied. Ten patients were above the age of 35 years and 38 were below the age of 35 years. Chorionic villus samples were obtained after 10th week of pregnancy through transabdominal approach. Cytogenetic cultures were set up both by the direct and routine methods.
  
  
  RESULTS
  Three out of the seven samples taken from expecting mothers aged above 35 and one culture from a patient aged less than 35, showed trisomy 21.
  
  
  CONCLUSIONS
  This study highlights the fact that incidence of chromosomal aberrations and the Down's syndrome in particular, increases with the advancing maternal age. Prenatal studies can therefore be utilized to decrease the incidence of various chromosomal abnormalities.
authors.affiliation: Department of Haematology and Genetics, Armed Forces Institute of Pathology, Rawalpindi.
authors.forename: T
authors.initials: T
authors.lastname: Jameel
authors.forename: Y
authors.initials: Y
authors.lastname: Rashid
authors.forename: M
authors.initials: M
authors.lastname: Anwar
authors.forename: N
authors.initials: N
authors.lastname: Sultana
authors.forename: M A
authors.initials: MA
authors.lastname: Waqar
authors.forename: M
authors.initials: M
authors.lastname: Saleem
mesh_terms: D000328:Adult; D015193:Chorionic Villi Sampling; D004314:Down Syndrome / Q000175:diagnosis* / Q000517:prevention & control; D005260:Female; D006801:Humans; D008423:Maternal Age; D008875:Middle Aged; D011247:Pregnancy; D011446:Prospective Studies