title: Plasma zinc concentrations of mothers and the risk of oral clefts in their children in Utah.
abstract: BACKGROUND
  The role of maternal zinc nutrition in human oral clefts (OCs) is unclear. We measured plasma zinc concentrations (PZn) of case and control mothers to evaluate the associations between PZn and risk of OCs with and without other malformations.
  
  
  METHODS
  Case mothers were ascertained by the Utah Birth Defects Network and control mothers were selected from Utah birth certificates by matching for child gender and delivery month and year. Maternal blood was collected >1 year after the last pregnancy. PZn was available for 410 case mothers who were divided into four subgroups: isolated cleft lip with or without cleft palate (CL/P-I, n = 231), isolated cleft palate (CP-I, n = 74), CL/P with other malformations (CLP-M, n = 42), and CP with other malformations (CP-M, n = 63). PZn was available for 447 control mothers. The mean age of children at blood sampling was 3.7 years for all cases combined and 4.3 years for controls.
  
  
  RESULTS
  Mean PZns of all groups were similar, and low PZn (<11.0 micromol/L) was found in 59% of cases and 62% of controls. Risk of OCs did not vary significantly across PZn quartiles for the four subgroups individually and all OC groups combined.
  
  
  CONCLUSIONS
  We previously reported that poor maternal zinc status was a risk factor for OCs in the Philippines, where OC prevalence is high and maternal PZn is low. In Utah, however, no such association was found, suggesting that poor maternal zinc status may become a risk factor only when zinc status is highly compromised.
authors.affiliation: Department of Nutrition and Food Sciences, Utah State University, Logan, UT, USA.
authors.forename: Ronald G
authors.initials: RG
authors.lastname: Munger
authors.forename: Tsunenobu
authors.initials: T
authors.lastname: Tamura
authors.forename: Kelley E
authors.initials: KE
authors.lastname: Johnston
authors.forename: Marcia L
authors.initials: ML
authors.lastname: Feldkamp
authors.forename: Roxane
authors.initials: R
authors.lastname: Pfister
authors.forename: John C
authors.initials: JC
authors.lastname: Carey
mesh_terms: D000015:Abnormalities, Multiple / Q000453:epidemiology; D000328:Adult; D016022:Case-Control Studies; D002648:Child; D002675:Child, Preschool; D002971:Cleft Lip / Q000453:epidemiology / Q000209:etiology; D002972:Cleft Palate / Q000453:epidemiology / Q000209:etiology*; D005260:Female; D006801:Humans; D039382:Maternal Nutritional Physiological Phenomena; D009748:Nutrition Disorders / Q000097:blood / Q000150:complications / Q000453:epidemiology; D011247:Pregnancy; D011248:Pregnancy Complications / Q000097:blood / Q000453:epidemiology; D011297:Prenatal Exposure Delayed Effects / Q000097:blood / Q000209:etiology; D012306:Risk; D014589:Utah / Q000453:epidemiology; D055815:Young Adult; D015032:Zinc / Q000097:blood* / Q000172:deficiency
chemical_list: D015032:Zinc