"To date, only one study of the link between breastfeeding and SIDS has used
dose-response definitions and appropriate recruitment strategies.
Fredrickson, Sorenson, Biddle and Kotelchuck (1993) utilized data from the
National Maternal and Infant Health Survey of 10,000 births and 6000 deaths
of babies born during 1988-1989.  Their final sample included 7102 controls,
499 SIDS deaths, and 584 non-SIDS deaths.  Their analysis used a consistent
dosage-definition of breastfeeding and controlled for major confounders
(birth weight, maternal age/race/education/postnatal smoking/prenatal
cocaine use/lack of private insurance, household smoking, day care, and
household size).  The found that "the risk of SIDS for black infants
increased by 1.19 for every month of not breastfeeding, and 2.13 for every
month of not exclusively breastfeeding.  Among white infants, the risk
increased by 1.19 and 2.0 times, respectively.  These associations remained
even when deaths within the first month of life were excluded.  A similar
protective association existed also for non-SIDS deaths" (Fredrickson et
al., 1993:460)."

This excerpt is from:

McKenna, James J., and Nicole J. Bernshaw
        1995  Breastfeeding and Infant-Parent Co-Sleeping as Adaptive
Strategies: Are They Protective Against SIDS?  In Patricia Stuart-Macadam
and Katherine A. Dettwyler (editors) Breastfeeding: Biocultural
Perspectives.  New York: Aldine de Gruyter.  Pp. 265-303.

The paragraphs quoted are from p. 273-274.

The Fredrickson et al. reference is:

Fredrickson, D.D., J.R. Sorenson, A.K. Biddle, and M. Kotelchuck  1993
Relationship between sudden infant death syndrome and breastfeeding
intensity and duration.  American Journal of Diseases of Children 147(May):460.

This is an abstract of a paper given at professional meetings.  I can put my
finger on the abstract right this second (it's in my office *somewhere*
though!), but it says that for every month of exclusive breastfeeding, you
cut the bottle-fed risk of SIDS in half.  So one month of exclusive
breastfeeding means you have 1/2 the risk, two months of exclusive
breastfeeding means you have 1/4 the risk, three months of exsclusive
breastfeeding means you have 1/8 the risk, etc.  By the time you get to six
months of exclusive breastfeeding, there basically are no children dying of
SIDS.

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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