title: [The association between maternal age and congenital malformations].
abstract: BACKGROUND
  There is an association between extreme maternal ages and the risk of congenital malformations. This is specially true for chromosomal abnormalities among women of advanced ages and disruptive malformation among teenage mothers.
  
  
  OBJECTIVE
  To determine the association between maternal ages and incidence of congenital malformations at the obstetric ward of a clinical hospital. To compare these figures with those of Chile.
  
  
  METHODS
  The hospital registries of the Latin American Collaborative Study of Congenital Malformations (ECLAMC) between 1996 and 2005, were consulted. This is a database of all malformations detected in newborns at the hospital.
  
  
  RESULTS
  An overall prevalence of malformations of 8,4% was detected at the hospital. There is a significantly lower frequency of mothers aged less than 20 years than in the rest of Chile. Mothers aged between 20 and 29 years have the lower frequency of malformed children. Women aged less than 20 years and over 39 years of age account for 56% of malformed children. Maternal ages and the rates of malformations, increased in a parallel fashion at a rate of 0.2 years and 2.2 malformed children per 1,000 born alive, per calendar year, respectively.
  
  
  CONCLUSIONS
  The association between prevalence rates of congenital malformations and maternal age is U shaped with a higher proportion of malformed children among women aged less than 20 years or more than 39 years.
authors.affiliation: Unidad de Neonatología, Hospital Clínico, Universidad de Chile, Santiago, Chile. julionazer@mi-mail.cl
authors.forename: Julio
authors.initials: J
authors.lastname: Nazer H
authors.forename: Lucía
authors.initials: L
authors.lastname: Cifuentes O
authors.forename: Alfredo
authors.initials: A
authors.lastname: Aguila R
authors.forename: Pilar
authors.initials: P
authors.lastname: Ureta L
authors.forename: María Piedad
authors.initials: MP
authors.lastname: Bello P
authors.forename: Francisca
authors.initials: F
authors.lastname: Correa C
authors.forename: Francisco
authors.initials: F
authors.lastname: Melibosky R
mesh_terms: D000293:Adolescent; D000328:Adult; D002677:Chile / Q000453:epidemiology; D000013:Congenital Abnormalities / Q000453:epidemiology*; D005260:Female; D006801:Humans; D007231:Infant, Newborn; D008423:Maternal Age; D008875:Middle Aged; D011247:Pregnancy; D015995:Prevalence; D012042:Registries / Q000706:statistics & numerical data; D012307:Risk Factors