title: Consanguinity and pregnancy outcomes in a multi-ethnic, metropolitan European population.
abstract: OBJECTIVE
  The aim of the present study was to assess the risk of major anomalies in the offspring of consanguineous couples, including data on the prenatal situation.
  
  
  METHODS
  Over 20 years (1993-2012), 35,391 fetuses were examined by prenatal sonography. In 675 cases (1.9%), parents were consanguineous, with 307 couples (45.5%) related as first cousins, 368 couples (54.5%) beyond first cousins. Detailed information was retrieved on 31,710 (89.6%) fetuses, (consanguineous 568: 1.8%).
  
  
  RESULTS
  Overall prevalence of major anomalies among fetuses with non-consanguineous parents was 2.9% (consanguineous, 10.9%; first cousins, 12.4%; beyond first cousins, 6.5%). Adjusting the overall numbers for cases having been referred because of a previous index case, the prevalences were 2.8% (non-consanguineous) and 6.1% (consanguineous) (first cousin, 8.5%; beyond first cousin, 3.9%). Further adjustment for differential rates of trisomic pregnancies indicated 2.0%/5.9% congenital anomalies (non-consanguineous/consanguineous groups), that is, a consanguinity-associated excess of 3.9%, 6.1% in first cousin progeny and 1.9% beyond first cousin.
  
  
  CONCLUSIONS
  The prevalence of major fetal anomalies associated with consanguinity is higher than in evaluations based only on postnatal life. It is important that this information is made available in genetic counselling programmes, especially in multi-ethnic and multi-religious communities, to enable couples to make informed decisions.
authors.affiliation: Center for Prenatal Diagnosis and Human Genetics, Berlin, Germany.
authors.forename: Rolf
authors.initials: R
authors.lastname: Becker
authors.forename: Thomas
authors.initials: T
authors.lastname: Keller
authors.forename: Rolf-Dieter
authors.initials: RD
authors.lastname: Wegner
authors.forename: Heidemarie
authors.initials: H
authors.lastname: Neitzel
authors.forename: Markus
authors.initials: M
authors.lastname: Stumm
authors.forename: Ute
authors.initials: U
authors.lastname: Knoll
authors.forename: Markus
authors.initials: M
authors.lastname: Stärk
authors.forename: Heiner
authors.initials: H
authors.lastname: Fangerau
authors.forename: Alan
authors.initials: A
authors.lastname: Bittles
mesh_terms: D000293:Adolescent; D000328:Adult; D003241:Consanguinity; D005006:Ethnicity / Q000706:statistics & numerical data*; D005060:Europe / Q000453:epidemiology; D005260:Female; D005858:Germany / Q000453:epidemiology; D006801:Humans; D007231:Infant, Newborn; D008297:Male; D008875:Middle Aged; D011247:Pregnancy; D011256:Pregnancy Outcome / Q000453:epidemiology*; D015995:Prevalence; D014505:Urban Population / Q000706:statistics & numerical data; D055815:Young Adult