title: [Prevalence and secular trend of Down syndrome in Asturias (Spain), 1990-2004].
abstract: OBJECTIVE
  Down syndrome (DS) is the most frequent chromosomal abnormality and bears a severe associated morbidity. Our goal was to describe trends in the prevalence of DS in Asturias (Spain).
  
  
  METHODS
  Data from the Registry of Congenital Defects were analyzed, including births and induced abortions, between 1990 and 2004.
  
  
  RESULTS
  Out of a total 103 452 births, 356 chromosomal anomalies had been registered (176 births and 180 induced abortions) and there were 210 DS (119 live births, two stillbirths and 89 induced abortions). Total prevalence assessment showed an important upward trend over time in both cases. The prevalence of total chromosomal abnormalities increased from 22 cases per 10 000 births in 1990 to 48,6 in 2004 and the DS prevalence increased from 13 to 29,1. Furthermore, 63% of DS births presented one or more associated defects, cardiac and digestive tract defects being the most frequent.
  
  
  CONCLUSIONS
  Changes in maternal age and prenatal screening have influenced DS prevalence and trends.
authors.affiliation: Consejería de Salud y Servicios Sanitarios, Servicio de Salud del Principado de Asturias, Oviedo, España.
authors.forename: Carmen
authors.initials: C
authors.lastname: Mosquera Tenreiro
authors.forename: Fernando
authors.initials: F
authors.lastname: Ariza Hevia
authors.forename: Cristina
authors.initials: C
authors.lastname: Rodríguez Dehli
authors.forename: Joaquín
authors.initials: J
authors.lastname: Fernández Toral
authors.forename: Enrique
authors.initials: E
authors.lastname: García López
authors.forename: Isolina
authors.initials: I
authors.lastname: Riaño Galán