What are safe sleeping arrangements for infants?

SIDS is defined as the sudden death of an infant aged <1 year of age that remains unexplained after a thorough investigation. The SIDS mortality rate is 0.57 per 1000 infants, with peak incidence among 1- to 5-month-olds. Non-supine sleep position and parental tobacco use are established risk factors for SIDS and therefore are not explicitly addressed in this review. Using the 9 best-designed case-control studies published to date, each of which used multivariate analysis to control for infant sleep position and parental tobacco use (among other confounders), we evaluated co-sleeping, room sharing, sleep surfaces, and bedding accessories as risk factors for SIDS (TABLE). A number of factors complicated this review. First, although all studies evaluated infants through 1 year of age, some excluded infants <7 days or <28 days old. Second, studies examined different sleep periods; 2 focused on usual sleeping arrangements, 5 on sleeping arrangement immediately prior to death, and 2 evaluated both usual and last sleep arrangements. Third, variations in definitions of each risk factor and differences in the confounders controlled for made comparing studies challenging. Fourth, given the difficulty in studying infant deaths, the best evidence available comes from case-control studies. Co-sleeping. Overall, 5 of 6 studies demonstrated co-sleeping to be an independent risk factor for SIDS (odds ratio [OR]=2.0-16.5), especially for infants younger than 11 weeks old. Four stratified analyses indicate that the risk of co-sleeping is greatest among infants of smokers (OR=4.6-17.7) as compared with infants of nonsmokers (OR=1.0-2.2). Some descriptive studies suggest potential benefits of cosleeping, such as improved breastfeeding and maternal-infant bonding, but these benefits have not been quantified. Room sharing. Three of 4 studies found that infants sleeping in separate rooms from their caregivers had a 3-fold increased risk of SIDS, while the fourth study found a 10-fold increased risk. One study found the risk was present in infants less than 20 weeks, but was inconclusive for those greater than 20 weeks. Sleep surface. All 4 studies evaluating sleep surface found a significantly increased risk of SIDS for infants sleeping on sofas or armchairs compared with infants sleeping in beds or cribs. Fifty-five of 772 total cases (7.1%) from the 4 studies slept on a non-bed surface compared with 8 of 1854 controls (0.4%). Bedding accessories. Two of 3 studies found pillow use unrelated to SIDS. The larger of 2 studies on duvet use found it to be a risk factor for SIDS (OR=1.82).