title: In utero Head Circumference is Associated with Childhood Allergy.
abstract: BACKGROUND
  Altered fetal growth is known to be associated with allergic disease. Specifically, increased head circumference at birth has been linked to asthma and elevated IgE. However, few studies have examined a link between early fetal anthropometry and allergic disease. The aim of this study was to examine head circumference at mid-gestation in children diagnosed with allergy.
  
  
  METHODS
  This was a retrospective cohort study, comprising pregnancies delivered between 10/2006 and 9/2010 at Nepean Hospital, Australia. Exclusion criteria were illegal drug use, alcohol consumption, gestation <35 weeks, and gestational hypertension. Pregnancy data were sourced from the Nepean Obstetric Database. Atopic diseases (asthma, atopic dermatitis, and IgE-mediated food allergy) were assessed by questionnaire at age 1-5 years. Infants from pregnancies with completed questionnaires, who also had a mid-gestation ultrasound scan, were included (N = 121). Multiple logistic regression techniques were used to model head circumference against the development of allergies.
  
  
  RESULTS
  Smaller head circumference at mid-gestation was associated with increased odds of allergic disease in children aged 1-5 years. A 1 mm smaller head circumference was associated with a 7% increased chance of allergies being later diagnosed, adjusted for gestation (95% CI: 1-14%, p = 0.036). Head circumference at mid-gestation was also inversely correlated with the presence of multiple atopic disease.
  
  
  CONCLUSIONS
  Smaller mid-gestational head circumference is associated with early childhood allergic disease, which suggests that fetal programing of allergic disease occurs before mid-gestation. This suggests that mediators such as brain-derived neurotrophic factor may be dysregulated early in utero in a milieu, which also predisposes to atopic disease.
authors.affiliation: Discipline of Obstetrics, Gynaecology and Neonatology, Charles Perkins Centre Nepean, Sydney Medical School Nepean, The University of Sydney , Penrith, NSW , Australia.
authors.forename: David P
authors.initials: DP
authors.lastname: Eviston
authors.affiliation: Discipline of Paediatrics and Child Health, Charles Perkins Centre Nepean, Sydney Medical School Nepean, The University of Sydney , Penrith, NSW , Australia.
authors.forename: Anna
authors.initials: A
authors.lastname: Minasyan
authors.affiliation: NHMRC Clinical Trials Centre, The University of Sydney , Camperdown, NSW , Australia.
authors.forename: Kristy P
authors.initials: KP
authors.lastname: Mann
authors.affiliation: Department of Allergy and Immunology, The Children's Hospital at Westmead, The University of Sydney , Westmeabd, NSW , Australia ; Discipline of Paediatrics and Child Health, The University of Sydney , Penrith, NSW , Australia.
authors.forename: Dianne E
authors.initials: DE
authors.lastname: Campbell
authors.affiliation: Discipline of Obstetrics, Gynaecology and Neonatology, Charles Perkins Centre Nepean, Sydney Medical School Nepean, The University of Sydney , Penrith, NSW , Australia ; Discipline of Paediatrics and Child Health, The University of Sydney , Penrith, NSW , Australia.
authors.forename: Ralph K
authors.initials: RK
authors.lastname: Nanan
keywords: allergy; developmental programming; fetus; head circumference; mid-gestation; ultrasound