Benefits and harms associated with the practice of bed sharing: a systematic review.
OBJECTIVE
To examine evidence of benefits and harms to children associated with bed sharing, factors (eg, smoking) altering bed sharing risk, and effective strategies for reducing harms associated with bed sharing.


METHODS
MEDLINE, CINAHL, Healthstar, PsycINFO, the Cochrane Library, Turning Research Into Practice, and Allied and Alternative Medicine databases between January 1993 and January 2005.


METHODS
Published, English-language records investigating the practice of bed sharing (defined as a child sharing a sleep surface with another individual) and associated benefits and harms in children 0 to 2 years of age.


METHODS
Any reported benefits or harms (risk factors) associated with the practice of bed sharing.


RESULTS
Forty observational studies met our inclusion criteria. Evidence consistently suggests that there may be an association between bed sharing and sudden infant death syndrome (SIDS) among smokers (however defined), but the evidence is not as consistent among nonsmokers. This does not mean that no association between bed sharing and SIDS exists among nonsmokers, but that existing data do not convincingly establish such an association. Data also suggest that bed sharing may be more strongly associated with SIDS in younger infants. A positive association between bed sharing and breastfeeding was identified. Current data could not establish causality. It is possible that women who are most likely to practice prolonged breastfeeding also prefer to bed share.


CONCLUSIONS
Well-designed, hypothesis-driven prospective cohort studies are warranted to improve our understanding of the mechanisms underlying the relationship between bed sharing, its benefits, and its harms.
Horsley
Tanya
T
Department of Pediatrics, University of Ottawa, and Department of Pediatrics, the Children's Hospital of Eastern Ontario, 401 Smyth Road, Ottawa, Ontario, Canada. thorsley@rcpsc.edu
Clifford
Tammy
T
Barrowman
Nicholas
N
Bennett
Susan
S
Yazdi
Fatemeh
F
Sampson
Margaret
M
Moher
David
D
Dingwall
Orvie
O
Schachter
Howard
H
Côté
Aurore
A
D001513:Beds; D002648:Child; D002668:Child Rearing; D006801:Humans; D007223:Infant; D009769:Object Attachment; D010287:Parent-Child Relations; D012307:Risk Factors; D012907:Smoking; D013398:Sudden Infant Death / Q000453:epidemiology / Q000209:etiology