Background

Non-supine infant sleep positions put infants at risk for sudden unexpected infant death (SUID). Disparities in safe sleep practices are associated with maternal income and race/ethnicity. The Special Supplemental Nutrition Program for Women, Infants and Children (WIC) is a nutrition supplement program for low-income (≤185% Federal Poverty Level) pregnant and postpartum women. Currently in Massachusetts, approximately 40% of pregnant/postpartum women are WIC clients. To inform the development of a SUID intervention strategy, the Massachusetts Department of Public Health (MDPH) investigated the association between WIC status and infant safe sleep practices among postpartum Massachusetts mothers using data from the Pregnancy Risk Assessment Monitoring System (PRAMS) survey.

Methods

PRAMS is an ongoing statewide health surveillance system of new mothers conducted by the MDPH in collaboration with the Centers for Disease Control and Prevention (CDC). PRAMS includes questions about infant sleep position and mothers’ prenatal WIC status. Risk Ratio (RR) and 95 percent confidence intervals (CI) were calculated for infant supine sleep positioning by WIC enrollment, yearly and in aggregate (2007–2010).

Results/Outcomes

The aggregate (2007–2010) weighted sample included 276,252 women (weighted n ≈ 69,063 women/year; mean survey response rate 69%). Compared to non-WIC mothers, WIC mothers were less likely to usually or always place their infants in supine sleeping positions [RR = 0.81 (95% CI: 0.80, 0.81)]. Overall, significant differences were found for each year (2007, 2008, 2009, 2010), and in aggregate (2007–2010) by WIC status.

Conclusion

Massachusetts WIC mothers more frequently placed their babies in non-supine positions than non-WIC mothers. While this relationship likely reflects the demographic factors associated with safe sleep practices (e.g., maternal income and race/ethnicity), the finding informed the deployment of an intervention strategy for SUID prevention. Given WIC’s statewide infrastructure and the large proportion of pregnant/postpartum women in Massachusetts that are enrolled in WIC, a WIC-based safe sleep intervention may be an effective SUID reduction strategy with potential national application.