title: Prevalence of Down's syndrome in a pregnant population in Finland.
abstract: The characteristics of the Finnish parturient have changed in recent years. The mean age of mothers at first delivery is now 29.3 years and the number of women > 35 years of age has increased to 19%. This shift has led to an increase in the prevalence of Down's syndrome. Between 1 January 2002 and 31 December 2006, there were 795 cases of Down's syndrome (27/10,000) in the Finnish Register of Congenital Malformations. The distribution of Down's syndrome in terminated pregnancies and newborns was analyzed in 5-year periods based on maternal age. The distribution of Down's syndrome cases in younger women (< 35 years) and in older women (> or =35 years) at the time of delivery was compared. The majority of new Down's syndrome cases occurred in the group having older women (61.1%), even though 35 years is the arbitrary threshold.
authors.affiliation: Department of Obstetrics and Gynecology, National Institute for Health and Welfare, Helsinki, Finland.
authors.forename: Jaana
authors.initials: J
authors.lastname: Marttala
authors.forename: Outi
authors.initials: O
authors.lastname: Yliniemi
authors.forename: Mika
authors.initials: M
authors.lastname: Gissler
authors.forename: Pentti
authors.initials: P
authors.lastname: Nieminen
authors.forename: Markku
authors.initials: M
authors.lastname: Ryynanen
mesh_terms: D000022:Abortion, Spontaneous / Q000453:epidemiology; D000032:Abortion, Therapeutic / Q000706:statistics & numerical data; D000328:Adult; D016001:Confidence Intervals; D004314:Down Syndrome / Q000175:diagnosis* / Q000453:epidemiology*; D005260:Female; D046689:Fetal Mortality; D005387:Finland; D005500:Follow-Up Studies; D005820:Genetic Testing; D006306:Health Surveys; D006801:Humans; D007231:Infant, Newborn; D008423:Maternal Age; D008875:Middle Aged; D011247:Pregnancy; D011296:Prenatal Diagnosis / Q000379:methods; D015995:Prevalence; D011336:Probability; D012042:Registries; D018570:Risk Assessment