title: Sex differences in the association between foetal growth and child attention at age four: specific vulnerability of girls.
abstract: BACKGROUND
  Recent evidence suggests that impaired foetal growth may provide an early indication of increased risk of child attention problems. However, despite both foetal growth and child attention problems differing by sex, few studies have examined sex differences in this association. Furthermore, no studies have been conducted in low- and middle-income countries, where there are higher rates of perinatal problems. This study aimed to test for sex differences in the association between foetal growth indices and attention problems at age four, in a large, prospective birth cohort from a middle-income country.
  
  
  METHODS
  A total of 3,749 neonates from the 2004 Pelotas birth cohort (Brazil) with foetal growth indices collected at birth [low birthweight (LBW), small-for-gestational age (SGA), head circumference (HC), head circumference-to-abdominal circumference ratio (HC/AC) and ponderal index (PI)], were assessed for attention problems using the Child Behaviour Checklist at age four. Ordinal logistic regression with successive adjustment for maternal, demographic, gestational, perinatal and child nutrition/mother-child morbidity, was conducted separately for girls and boys.
  
  
  RESULTS
  In girls, attention difficulties were associated with being born SGA (OR = 1.40, CI = 1.08-1.82, p = .012), with a small HC (OR = 1.52, CI = 1.11-2.08, p = .009), or with a low PI (OR = 1.29, CI = 1.08-1.54, p = .005). There were no associations identified between attention difficulties and any foetal growth indices in boys.
  
  
  CONCLUSIONS
  Our results show that girls with impaired foetal growth may be particularly at risk of attention difficulties in childhood. This is consistent with emerging research that female foetuses may be more vulnerable to certain suboptimal intrauterine environments, inducing epigenetic changes that lead to disturbed growth and long-term developmental impairment.
authors: Department of Psychiatry, Oxford University, Oxford, UK.
authors: Elizabeth
authors: E
authors: Murray
authors: Postgraduate Program in Epidemiology, Federal University of Pelotas, Pelotas, Brazil.|Department of Preventive Medicine, University of São Paulo, São Paulo, Brazil.
authors: Alicia
authors: A
authors: Matijasevich
authors: Postgraduate Program in Epidemiology, Federal University of Pelotas, Pelotas, Brazil.
authors: Iná S
authors: IS
authors: Santos
authors: Postgraduate Program in Epidemiology, Federal University of Pelotas, Pelotas, Brazil.
authors: Aluísio J D
authors: AJ
authors: Barros
authors: Postgraduate Program in Epidemiology, Federal University of Pelotas, Pelotas, Brazil.
authors: Luciana
authors: L
authors: Anselmi
authors: Postgraduate Program in Epidemiology, Federal University of Pelotas, Pelotas, Brazil.|Postgraduate Program in Health and Behavior, Catholic University of Pelotas, Pelotas, Brazil.
authors: Fernando C
authors: FC
authors: Barros
authors: Department of Psychiatry, Oxford University, Oxford, UK.
authors: Alan
authors: A
authors: Stein
mesh_terms: D001288:Attention / Q000502:physiology*; D001289:Attention Deficit Disorder with Hyperactivity / Q000453:epidemiology* / Q000209:etiology; D001938:Brazil / Q000453:epidemiology; D002657:Child Development / Q000502:physiology*; D002675:Child, Preschool; D005260:Female; D047109:Fetal Development / Q000502:physiology*; D005500:Follow-Up Studies; D006801:Humans; D007230:Infant, Low Birth Weight / Q000502:physiology*; D007231:Infant, Newborn; D007236:Infant, Small for Gestational Age / Q000502:physiology; D008297:Male; D012737:Sex Factors
keywords: Gender; head circumference; low birth weight; pelotas birth cohort; ponderal index; small-for-gestational age