title: Maternal smoking and urinary organ malformations.
abstract: BACKGROUND
  In order to investigate whether an earlier reported association between maternal smoking during pregnancy and urinary organ malformations could be confirmed, a study was made using Swedish health registries.
  
  
  METHODS
  Infants with kidney malformations (n = 483) and infants with other urinary organ malformations with no primary involvement of the kidney(s) (n = 719) were selected among 1117021 infants born 1983-1993 with known smoking exposure in early pregnancy.
  
  
  RESULTS
  A moderate statistically significant association between maternal smoking and kidney malformations was found (adjusted odds ratio [OR] = 1.22, 95% confidence interval [CI] : 1.00-1.48). With the exception of genetic renal polycystic disease, the main subgroups of kidney malformations showed similar OR. For other urinary organ malformations, no association with smoking could be detected (OR = 0.93, 95% CI: 0.79-1.11).
  
  
  CONCLUSIONS
  This study supports an association between maternal smoking during pregnancy and kidney malformations. No obvious confounders were detected but further work is needed before a causal inference can be made.
authors.affiliation: Tornblad Institute, Lund, Sweden.
authors.forename: K
authors.initials: K
authors.lastname: Källen
mesh_terms: D016001:Confidence Intervals; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D007231:Infant, Newborn; D007668:Kidney / Q000002:abnormalities; D007674:Kidney Diseases / Q000151:congenital / Q000453:epidemiology; D008297:Male; D016017:Odds Ratio; D011247:Pregnancy; D012042:Registries; D012189:Retrospective Studies; D012737:Sex Factors; D012907:Smoking / Q000453:epidemiology*; D013548:Sweden / Q000453:epidemiology; D014551:Urinary Tract / Q000002:abnormalities*; D014570:Urologic Diseases / Q000151:congenital* / Q000453:epidemiology*