title: Maternal underweight and obesity and risk of orofacial clefts in a large international consortium of population-based studies.
abstract: Evidence on association of maternal pre-pregnancy weight with risk of orofacial clefts is inconsistent.
  
  
  
  Six large case-control studies of orofacial clefts from Northern Europe and the USA were included in analyses pooling individual-level data. Cases included 4943 mothers of children with orofacial clefts (cleft lip only: 1135, cleft palate with cleft lip: 2081, cleft palate only: 1727) and controls included 10 592 mothers of unaffected children. Association of orofacial cleft risk with pre-pregnancy maternal weight classified by level of body mass index (BMI, kg/m 2 ) was evaluated using logistic regression adjusting for multiple covariates.
  
  
  
  Cleft palate, both alone and with cleft lip (CP+/-CL), was associated with maternal class II+ pre-pregnancy obesity (≥ 35)compared with normal weight [adjusted odds ratio (aOR) = 1.36; 95% confidence interval (CI) = 1.16, 1.58]. CP+/-CL was marginally associated with maternal underweight (aOR = 1.16; 95% CI = 0.98, 1.36). Cleft lip alone was not associated with BMI.
  
  
  
  In this largest population-based study to date, we found an increased risk of cleft palate, with or without cleft lip, in class II+ obese mothers compared with normal-weight mothers; underweight mothers may also have an increased risk, but this requires further study. These results also suggest that extremes of weight may have a specific effect on palatal development.
authors.affiliation: Department of Nutrition, Dietetics, and Food Sciences, Utah State University, Logan, UT, USA.
authors.forename: Hebah
authors.initials: H
authors.lastname: Kutbi
authors.affiliation: Department of Health Management and Policy.
authors.forename: George L
authors.initials: GL
authors.lastname: Wehby
authors.affiliation: Department of Orthodontics.
authors.forename: Lina M
authors.initials: LM
authors.lastname: Moreno Uribe
authors.affiliation: Department of Epidemiology, University of Iowa, Iowa City, IA, USA.
authors.forename: Paul A
authors.initials: PA
authors.lastname: Romitti
authors.affiliation: Department of Pediatrics, Stanford University, Palo Alto, CA, USA.
authors.forename: Suzan
authors.initials: S
authors.lastname: Carmichael
authors.affiliation: Department of Pediatrics, Stanford University, Palo Alto, CA, USA.
authors.forename: Gary M
authors.initials: GM
authors.lastname: Shaw
authors.affiliation: Department of Epidemiology, University of North Carolina, Chapel Hill, NC, USA.
authors.forename: Andrew F
authors.initials: AF
authors.lastname: Olshan
authors.affiliation: Epidemiology Branch, National Institute of Environmental Health Sciences, Research Triangle Park, NC, USA.|Department of Public Health and Primary Health Care, University of Bergen, Bergen, Norway.
authors.forename: Lisa
authors.initials: L
authors.lastname: DeRoo
authors.affiliation: Centres for Disease Control and Prevention, Atlanta, GA, USA.
authors.forename: Sonja A
authors.initials: SA
authors.lastname: Rasmussen
authors.affiliation: Department of Pediatrics, University of Iowa Hospitals and Clinics, Iowa City, IA, USA.
authors.forename: Jeffrey C
authors.initials: JC
authors.lastname: Murray
authors.affiliation: Epidemiology Branch, National Institute of Environmental Health Sciences, Research Triangle Park, NC, USA.
authors.forename: Allen
authors.initials: A
authors.lastname: Wilcox
authors.affiliation: Department of Public Health and Primary Health Care, University of Bergen, Bergen, Norway.
authors.forename: Rolv T
authors.initials: RT
authors.lastname: Lie
authors.affiliation: Department of Nutrition, Dietetics, and Food Sciences, Utah State University, Logan, UT, USA.
authors.forename: Ronald G
authors.initials: RG
authors.lastname: Munger
mesh_terms: D000328:Adult; D015992:Body Mass Index; D016022:Case-Control Studies; D002971:Cleft Lip / Q000150:complications / Q000453:epidemiology*; D002972:Cleft Palate / Q000150:complications / Q000453:epidemiology*; D005060:Europe / Q000453:epidemiology; D005260:Female; D006801:Humans; D007231:Infant, Newborn; D007391:International Cooperation; D016015:Logistic Models; D008297:Male; D009035:Mothers; D009765:Obesity / Q000150:complications* / Q000453:epidemiology; D011247:Pregnancy; D012307:Risk Factors; D013851:Thinness / Q000150:complications* / Q000453:epidemiology; D014481:United States / Q000453:epidemiology; D055815:Young Adult
keywords: Cleft lip; case-control study; cleft palate; maternal weight; obesity; underweight