title: Do socio-economic inequalities in infant growth in rural India operate through maternal size and birth weight?
abstract: BACKGROUND
  In total, 3.1 million young children die every year from under-nutrition. Greater understanding of associations between socio-economic status (SES) and the biological factors that shape under-nutrition are required to target interventions.
  
  
  OBJECTIVE
  To establish whether SES inequalities in under-nutrition, proxied by infant size at 12 months, operate through maternal and early infant size measures.
  
  
  METHODS
  The sample comprised 347 Indian infants born in 60 villages in rural Andhra Pradesh 2005-2007. Structural equation path models were applied to decompose the total relationship between SES (standard of living index) and length and weight for age Z-scores (LAZ/WAZ) at 12 months into direct and indirect (operating through maternal BMI and height, birthweight Z-score and LAZ/WAZ at 6 months) paths.
  
  
  RESULTS
  SES had a direct positive association with LAZ (Standardised coefficient = 0.08, 95% CI = 0.02-0.13) and WAZ at age 12 months (Standardised coefficient = 0.08, 95% CI = 0.02-0.15). It also had additional indirect positive associations through increased maternal height and subsequently increased birthweight and WAZ/LAZ at 6 months, accounting for 35% and 53% of the total effect for WAZ and LAZ, respectively.
  
  
  CONCLUSIONS
  Findings support targeting evidence based growth interventions towards infants from the poorest families with the shortest mothers. Increasing SES can improve growth for two generations.
authors.affiliation: a Centre for Global Health and Human Development, School of Sport, Exercise and Health Sciences, Loughborough University , Loughborough , Leicestershire , UK .
authors.forename: Paula L
authors.initials: PL
authors.lastname: Griffiths
authors.affiliation: b National Institute of Nutrition, Indian Council of Medical Research , Hyderabad , India , and.
authors.forename: Nagalla
authors.initials: N
authors.lastname: Balakrishna
authors.affiliation: b National Institute of Nutrition, Indian Council of Medical Research , Hyderabad , India , and.
authors.forename: Sylvia
authors.initials: S
authors.lastname: Fernandez Rao
authors.affiliation: c MRC Human Nutrition Research, Elsie Widdowson Laboratory , Cambridge , UK.
authors.forename: William
authors.initials: W
authors.lastname: Johnson
mesh_terms: D001724:Birth Weight; D049628:Body Size; D006801:Humans; D007194:India / Q000453:epidemiology; D007223:Infant; D044342:Malnutrition / Q000453:epidemiology* / Q000209:etiology; D008962:Models, Theoretical; D009035:Mothers; D011203:Poverty; D012424:Rural Population / Q000706:statistics & numerical data; D012923:Social Class
keywords: Birthweight; infant growth; maternal BMI; maternal height; socio-economic status; structural equation modeling