An interesting Japanese study found a link between lack of breastfeeding
(less than one week vs. more than one week) and autism, and suggests that it
might be related to breastfeeding lowering the risk of pneumonia and other
infections that have been linked to autism.

Tanoue, Yoko and Susumu Oda
        1989  Weaning Time of Children with Infantile Autism.  Journal of
Autism and Developmental Disorders, 19(3):425-434.

I turned this up in a medline search for *any* research looking at whether
the outcome for autistic children who nurse for several years is better than
for autistic children who nurse very briefly or not at all, assuming a
genetic or prenatal cause of autism.  I haven't found anything on the topic
I was searching for at all, so if any one knows, please let me know.

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Katherine A. Dettwyler, Ph.D.                         email: [log in to unmask]
Anthropology Department                               phone: (409) 845-5256
Texas A&M University                                    fax: (409) 845-4070
College Station, TX  77843-4352