title: Head circumference of infants born to mothers with different educational levels; the Generation R Study.
abstract: OBJECTIVE
  Head circumference (HC) reflect growth and development of the brain in early childhood. It is unknown whether socioeconomic differences in HC are present in early childhood. Therefore, we investigated the association between socioeconomic position (SEP) and HC in early childhood, and potential underlying factors.
  
  
  METHODS
  The study focused on Dutch children born between April 2002 and January 2006 who participated in The Generation R Study, a population-based prospective cohort study in Rotterdam, The Netherlands. Maternal educational level was used as indicator of SEP. HC measures were concentrated around 1, 3, 6 and 11 months. Associations and explanatory factors were investigated using linear regression analysis, adjusted for potential mediators.
  
  
  RESULTS
  The study included 3383 children. At 1, 3 and 6 months of age, children of mothers with a low education had a smaller HC than those with a high education (difference at 1 month: -0.42 SD; 95% CI: -0.54,-0.30; at 3 months: -0.27 SD; 95% CI -0.40,-0.15; and at 6 months: -0.13 SD; 95% CI -0.24,-0.02). Child's length and weight could only partially explain the smaller HC at 1 and 3 months of age. At 6 months, birth weight, gestational age and parental height explained the HC differences. At 11 months, no HC differences were found.
  
  
  CONCLUSIONS
  Educational inequalities in HC in the first 6 months of life can be mainly explained by pregnancy-related factors, such as birth weight and gestational age. These findings further support public health policies to prevent negative birth outcomes in lower socioeconomic groups.
authors: The Generation R Study Group, Erasmus Medical Centre, Rotterdam, The Netherlands.
authors: Selma H
authors: SH
authors: Bouthoorn
authors: Frank J
authors: FJ
authors: van Lenthe
authors: Anita C S
authors: AC
authors: Hokken-Koelega
authors: Henriëtte A
authors: HA
authors: Moll
authors: Henning
authors: H
authors: Tiemeier
authors: Albert
authors: A
authors: Hofman
authors: Johan P
authors: JP
authors: Mackenbach
authors: Vincent W V
authors: VW
authors: Jaddoe
authors: Hein
authors: H
authors: Raat
mesh_terms: D002508:Cephalometry; D004522:Educational Status; D005191:Family Characteristics; D005260:Female; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D009035:Mothers; D009426:Netherlands; D011247:Pregnancy