Breast feeding and child behaviour in the Millennium Cohort Study
- 1National Perinatal Epidemiology Unit, University of Oxford, Oxford, UK
- 2Institute for Social and Economic Research, University of Essex, Colchester, UK
- 3Department of Epidemiology and Public Health, University College London, London, UK
- 4Mother and Infant Research Unit, University of York, UK
- Correspondence to Katriina Heikkilä, Finnish Institute of Occupational Health, Topeliuksenkatu 41 a A, 00250 Helsinki, Finland;
- Accepted 28 February 2011
- Published Online First 9 May 2011
Objective To examine whether breast feeding is associated with behavioural development in children aged 5 years.
Design The authors used data from a large, prospective, nationally representative UK cohort, the Millennium Cohort Study.
Participants 10 037 mother–child pairs from white ethnic background (9525 term and 512 preterm children) were included in the analyses.
Methods Duration of breast feeding (at all or exclusively) was ascertained from parental interview at study baseline, when the children were aged 9 months. Child behaviour was assessed using a parent-completed questionnaire, the Strengths and Difficulties Questionnaire (SDQ). The authors used logistic regression to investigate the associations of breastfeeding duration with abnormal parent-rated SDQ total and subscores at age 5 in term and preterm children separately.
Results Abnormal SDQ scores were less common in term children (n=1129/9525, 12%) than pre-term (n=78/512, 15%) children. Term children breast fed for 4 months or longer (n=2741/9525, 29%) had lower odds of an abnormal total SDQ score (multivariable-adjusted OR compared with never breastfed children (n=3292/9525, 35%) 0.67, 95% CI: 0.54 to 0.83). This effect was similar for all the SDQ subscores. In preterm children, longer duration of breast feeding was generally associated with lower odds of abnormal SDQ total and subscores but the effect estimates were imprecise. The associations between exclusive breast feeding and abnormal SDQ scores were similar to those of any breast feeding and abnormal SDQ scores.
Conclusions The findings suggest that, at least in term children, longer duration of breast feeding is associated with fewer parent-rated behavioural problems in children aged 5 years.
Funding This paper reports on an independent study which was funded by the Policy Research Programme in the Department of Health, UK. The views expressed are not necessarily those of the Department. The MCS was funded by the Economic and Social Research Council, UK. KH and MAQ were funded by the Department of Health. AS and YK were funded in part by the UK Economic and Social Research Council Centre for Lifecourse Studies in Society and Health (grant number RES-596-28-0001). MJR was funded by the University of York.
Competing interests None.
Ethics approval The Millennium Cohort Study was approved by the London Multicentre Research Ethics Committee.
Provenance and peer review Not commissioned; externally peer reviewed.