title: [Urinary tract malformations in newborns at the Clinical Maternity Hospital of the University of Chile].
abstract: BACKGROUND
  The prevalence of urinary malformations at birth is steadily increasing, probably due to the availability of better diagnostic techniques.
  
  
  OBJECTIVE
  To assess the prevalence of renal agenesis, hidroureteronephrosis and polycystic kidney at birth in the obstetric wards of the University of Chile Clinical Hospital.
  
  
  METHODS
  As a part of the Latin American Collaborative Study of Congenital Malformations, 54.039 consecutive births at the Maternity, between January 1982 and December 1997, were studied.
  
  
  RESULTS
  Eighty three newborns had urinary tract malformations (15.3/10,000). Fourteen (2.6/10,000) had renal agenesis, 34 (6.3/10,000) had hidroureteronephrosis and 35 (6.5/10,000) had polycystic kidney. Eleven percent of these children were stillbirths and 35% died in the first days of life. Fifty six percent were male, 34% female and 10% had ambiguous sex. Mean birth weight was 2750 g, mean gestational age was 35.4 weeks and mean maternal age was 28 years old. Twenty three percent of mothers had a history of previous abortions, 8% had a history of stillbirths and 10% a history of metrorrhagia during the first trimester of pregnancy. Twenty five percent of children had a relative with a malformation and 48 children had other associated malformations such as pulmonary hypoplasia, external malformations caused by extreme oligoamnios or internal malformations such as utereral, urinary bladder; uretral or external genitalia agenesis.
  
  
  CONCLUSIONS
  The prevalence of urinary malformations in this hospital was higher than in other hospitals participating in the collaborative study. This difference could be due to an under registration of malformations in other hospitals.
authors.affiliation: Maternidad Hospital Clínico Universidad de Chile, Santigo de Chile.
authors.forename: J
authors.initials: J
authors.lastname: Nazer
authors.forename: P
authors.initials: P
authors.lastname: Fernández
authors.forename: C
authors.initials: C
authors.lastname: Silva
mesh_terms: D002677:Chile; D000013:Congenital Abnormalities / Q000453:epidemiology; D005260:Female; D006771:Hospitals, Maternity; D006801:Humans; D007231:Infant, Newborn; D007668:Kidney / Q000002:abnormalities; D008297:Male; D007690:Polycystic Kidney Diseases / Q000151:congenital; D015995:Prevalence; D014551:Urinary Tract / Q000002:abnormalities*