Duration of breast feeding and language ability in middle childhood.
There is controversy over whether increased breast-feeding duration has long-term benefits for language development. The current study examined whether the positive associations of breast feeding on language ability at age 5 years in the Western Australian Pregnancy (Raine) Cohort, were still present at age 10 years. The Raine Study is a longitudinal study of 2868 liveborn children recruited at approximately 18 weeks gestation. Breast-feeding data were based upon information prospectively collected during infancy, and were summarised according to four categories of breast-feeding duration: (1) never breast-fed, (2) breast-fed predominantly for <4 months, (3) breast-fed predominantly for 4-6 months, and (4) breast-fed predominantly for >6 months. Language ability was assessed in 1195 children at the 10 year follow-up (mean age = 10.58 years; standard deviation = 0.19) using the Peabody Picture Vocabulary Test - Revised (PPVT-R), which is based around a mean of 100 and a standard deviation of 15. Associations between breast-feeding duration and PPVT-R scores were assessed before and after adjustment for a range of sociodemographic, obstetric and psychosocial covariates. Analysis of variance revealed a strong positive association between the duration of predominant breast feeding and PPVT-R at age 10 years. A multivariable linear regression analysis adjusted for covariates and found that children who were predominantly breast-fed for >6 months had a mean PPVT-R score that was 4.04 points higher than children who were never breast-fed. This compared with an increase of 3.56 points at age 5 years. Breast feeding for longer periods in early life has a positive and statistically-independent effect on language development in middle childhood.
Telethon Institute for Child Health Research, Centre for Child Health Research, The University of Western Australia, Perth, Western Australia, Australia. awhitehouse@ichr.uwa.edu.au
Andrew J O
AJ
Whitehouse
Monique
M
Robinson
Jianghong
J
Li
Wendy H
WH
Oddy
D000328:Adult; D001942:Breast Feeding; D002648:Child; D002675:Child, Preschool; D004522:Educational Status; D005260:Female; D006801:Humans; D007223:Infant; D007804:Language Development; D008137:Longitudinal Studies; D008297:Male; D011247:Pregnancy; D012044:Regression Analysis; D012931:Social Environment; D011795:Surveys and Questionnaires; D013997:Time Factors; D014904:Western Australia