Stephen J.LurieMD, PhD, Senior EditorIndividualAuthor
To the Editor: Dr Mortensen and colleagues1 report a positive association between duration
of maternal breastfeeding and the infants' later IQ scores as young adults.
However, they fail to examine important confounders associated with breastfeeding,
including maternal depression, alcohol abuse, and quality of the marital relationship.
Any one of these variables, which often interact and occur together, could
be associated with the mother's choice not to breastfeed or to terminate breastfeeding
early. These variables are also associated with offspring depression and subsequent
poor performance in school, work, or on IQ tests as young adults.2,3
Weissman MM, Weissman J. Breastfeeding and Later Intelligence. JAMA. 2002;288(7):828-830. doi:10.1001/jama.288.7.828