OBJECTIVE:
To describe the prevalence and associations of bed– and sofa–sharing in a biethnic UK birth cohort.
METHODS:
We surveyed 3082 participants in the Born in Bradford birth cohort study by using a telephone interview when infants were aged 2 to 4 months. We asked families about sleep surface sharing behaviors, and other sudden unexpected death in infancy (SUDI)-related behaviors.
RESULTS:
There were 15.5% of families that had ever bed-shared, 7.2% of families regularly bed-shared, and 9.4% of families had ever sofa-shared with their infants; 1.4% reported both. Regular bed-sharers were more commonly Pakistani (adjusted odds ratio [aOR] = 3.02, 95% confidence interval [CI] 1.96-4.66), had further or higher educational qualifications (aOR = 1.62, 95% CI 1.03-2.57), or breastfed for at least 8 weeks (aOR = 3.06, 95% CI 2.00-4.66). The association between breastfeeding and bed–sharing was greater among white British than Pakistani families. Sofa–sharing occurred in association with smoking (aOR = 1.79, 95% CI 1.14-2.80) and breastfeeding for more than 8 weeks (aOR = 1.76, 95% CI 1.19-2.58), and was less likely in Pakistani families (aOR = 0.21, 95% CI 0.14-0.31), or single-parent families (aOR = 0.50, 95% CI 0.29-0.87).
CONCLUSIONS:
The data confirm that bed–sharing and sofa–sharing are distinct practices, which should not be combined in studies of unexpected infant deaths as a single exposure. The determinants of sleep-surface sharing differ between the UK Pakistani and UKmajority communities, and from those of US minority communities. Caution is needed in generalizing SUDI/SIDS risk factors across populations with differing risk factor profiles, and care should be taken in adopting SUDI/SIDS reduction guidelines from other contexts.
