Breastfeeding for longer means fewer behavioral problems
MedWire News: Infants who are breastfed for at least 4 months are less likely to develop behavioral abnormalities by the age of 5 years than those who are not breastfed, show UK study results.
The finding relates to children born at term as the results for preterm infants in the study cohort were unclear, write the researchers.
"Behavioral problems," explain the researchers, "have a negative impact on the child's development and interfere with the child's or their family's everyday life," they write in the Archives of Disease in Childhood.
The group used data for 10,037 mother-child pairs from the UK Millennium Cohort Study that included an evaluation of child behavior at 9 months and 5 years using the parent-completed Strengths and Difficulties Questionnaire (SDQ).
A total of 9525 children were born at term, and breastfeeding was equally common among term and preterm infants, at 65% in both groups. In all, 29% of term and 21% of preterm infants were breastfed for at least 4 months (median=9.8 and 9.6 months, respectively).
In term infants, any breastfeeding was associated with lower odds of an abnormal SDQ score, with a nonsignificant 17% reduced risk in those breastfed for less than 2.0 months, a nonsignificant 36% reduced risk in those breastfed for 2.0-3.9 months, and a significant 64% reduced risk in those breastfed for at least 4.0 months.
The team then adjusted the analysis for potentially confounding factors including household socioeconomic position and mother's education, mother-baby attachment (as measured by the Condon scale), and the infant's birth order.
The association between breastfeeding up to the age of 4 months and abnormal behavior was attenuated in this adjusted analysis. However, breastfeeding for 4 months or longer remained significantly associated with lower odds for abnormal behavior by 5 years of age, reducing the risk by 33%, compared with no breastfeeding.
The evidence for an association between breastfeeding and behavioral problems in preterm infants was not substantial, writes the research team.
"Our results provide even more evidence for the benefits of breastfeeding," said lead author Maria Quigley (Oxford University, England).
One possible explanation for the finding is that the essential fatty acids contained in breast milk have an important role in the development and function of the brain and central nervous system. But these are also now commonly found in formula milk, remarks the team.
The supposition that breastfeeding leads to more interaction between mother and child and enables the child to learn acceptable behaviors is also challenged in these results as the mother-baby interaction (Condon scale) was adjusted for in the analysis.
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By Sarah Guy