abstract
CONTEXT: Benefits of breastfeeding include lower risk of postneonatal
mortality. However, it is unclear whether breastfeeding specifically
lowers sudden infant death syndrome (SIDS) risk, because study results
have been conflicting.
OBJECTIVE: To perform a meta-analysis to measure the association
between breastfeeding and SIDS.
METHODS: We identified 288 studies with data on breastfeeding and
SIDS through a Medline search (1966 –2009), review articles, and metaanalyses.
Twenty-four original case-control studies were identified that
provided data on the relationship between breastfeeding and SIDS risk.
Two teams of 2 reviewers evaluated study quality according to preset
criteria; 6 studies were excluded, which resulted in 18 studies for
analysis. Univariable and multivariable odds ratios were extracted. A
summary odds ratio (SOR) was calculated for the odds ratios by using
the fixed-effect and random-effect inverse-variance methods of metaanalysis.
The Breslow-Day test for heterogeneity was performed.
RESULTS: For infants who received any amount of breast milk for any
duration, the univariable SOR was 0.40 (95% confidence interval [CI]:
0.35– 0.44), and the multivariable SOR was 0.55 (95% CI: 0.44 – 0.69). For
any breastfeeding at 2 months of age or older, the univariable SOR was
0.38 (95% CI: 0.27– 0.54). The univariable SOR for exclusive breastfeeding
of any duration was 0.27 (95% CI: 0.24 – 0.31).
CONCLUSIONS: Breastfeeding is protective against SIDS, and this effect
is stronger when breastfeeding is exclusive. The recommendation
to breastfeed infants should be included with other SIDS risk-reduction
messages to both reduce the risk of SIDS and promote breastfeeding
for its many other infant and maternal health