title: Antenatal and early infant predictors of postnatal growth in rural Vietnam: a prospective cohort study.
abstract: OBJECTIVE
  To determine which antenatal and early-life factors were associated with infant postnatal growth in a resource-poor setting in Vietnam.
  
  
  METHODS
  Prospective longitudinal study following infants (n=1046) born to women who had previously participated in a cluster randomised trial of micronutrient supplementation (ANZCTR:12610000944033), Ha Nam province, Vietnam. Antenatal and early infant factors were assessed for association with the primary outcome of infant length-for-age z scores at 6 months of age using multivariable linear regression and structural equation modelling.
  
  
  RESULTS
  Mean length-for-age z score was -0.58 (SD 0.94) and stunting prevalence was 6.4%. Using structural equation modelling, we highlighted the role of infant birth weight as a predictor of infant growth in the first 6 months of life and demonstrated that maternal body mass index (estimated coefficient of 45.6 g/kg/m(2); 95% CI 34.2 to 57.1), weight gain during pregnancy (21.4 g/kg; 95% CI 12.6 to 30.1) and maternal ferritin concentration at 32 weeks' gestation (-41.5 g per twofold increase in ferritin; 95% CI -78 to -5.0) were indirectly associated with infant length-for-age z scores at 6 months of age via birth weight. A direct association between 25-(OH) vitamin D concentration in late pregnancy and infant length-for-age z scores (estimated coefficient of -0.06 per 20 nmol/L; 95% CI -0.11 to -0.01) was observed.
  
  
  CONCLUSIONS
  Maternal nutritional status is an important predictor of early infant growth. Elevated antenatal ferritin levels were associated with suboptimal infant growth in this setting, suggesting caution with iron supplementation in populations with low rates of iron deficiency.
authors.affiliation: Department of Medicine, Doherty Institute, University of Melbourne, Parkville, Victoria, Australia.
authors.forename: Sarah
authors.initials: S
authors.lastname: Hanieh
authors.affiliation: Research and Training Centre for Community Development (RTCCD), Hanoi, Vietnam.
authors.forename: Tran T
authors.initials: TT
authors.lastname: Ha
authors.affiliation: Centre for Molecular, Environmental, Genetic and Analytic Epidemiology, Melbourne School of Population and Global Health, University of Melbourne, Parkville, Victoria, Australia.
authors.forename: Alysha M
authors.initials: AM
authors.lastname: De Livera
authors.affiliation: Centre for Molecular, Environmental, Genetic and Analytic Epidemiology, Melbourne School of Population and Global Health, University of Melbourne, Parkville, Victoria, Australia.
authors.forename: Julie A
authors.initials: JA
authors.lastname: Simpson
authors.affiliation: Research and Training Centre for Community Development (RTCCD), Hanoi, Vietnam.
authors.forename: Tran T
authors.initials: TT
authors.lastname: Thuy
authors.affiliation: Provincial Centre of Preventive Medicine, Ha Nam Province, Vietnam.
authors.forename: Nguyen C
authors.initials: NC
authors.lastname: Khuong
authors.affiliation: Provincial Centre of Preventive Medicine, Ha Nam Province, Vietnam.
authors.forename: Dang D
authors.initials: DD
authors.lastname: Thoang
authors.affiliation: Research and Training Centre for Community Development (RTCCD), Hanoi, Vietnam The Jean Hailes Research Unit, School of Public Health and Preventive Medicine, Monash University, Melbourne, Victoria, Australia.
authors.forename: Thach D
authors.initials: TD
authors.lastname: Tran
authors.affiliation: Research and Training Centre for Community Development (RTCCD), Hanoi, Vietnam.
authors.forename: Tran
authors.initials: T
authors.lastname: Tuan
authors.affiliation: The Jean Hailes Research Unit, School of Public Health and Preventive Medicine, Monash University, Melbourne, Victoria, Australia.
authors.forename: Jane
authors.initials: J
authors.lastname: Fisher
authors.affiliation: Department of Medicine, Doherty Institute, University of Melbourne, Parkville, Victoria, Australia The Victorian Infectious Diseases Service, Royal Melbourne Hospital, Parkville, Victoria, Australia.
authors.forename: Beverley-Ann
authors.initials: BA
authors.lastname: Biggs
mesh_terms: D000328:Adult; D001827:Body Height / Q000502:physiology*; D002657:Child Development / Q000502:physiology*; D015331:Cohort Studies; D019587:Dietary Supplements; D005260:Female; D006130:Growth Disorders / Q000209:etiology / Q000517:prevention & control; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008137:Longitudinal Studies; D008297:Male; D009752:Nutritional Status; D011203:Poverty; D011247:Pregnancy; D011446:Prospective Studies; D012307:Risk Factors; D012424:Rural Population; D014744:Vietnam / Q000453:epidemiology
keywords: Antenatal iron; Growth; Infant; Stunting