The effect of swaddling on infant sleep and arousal: A systematic review and narrative synthesis

To explore the effect of swaddling on infant sleep and arousal in infants under 12 months of age we conducted a systematic review of the evidence published over the past 15 years since the review of van Sleuwen et al. (1). This previous review concluded that swaddling infants above the waist increased sleep duration, reduced motor activity and startles, and lowered heart rate, however swaddling was not found to affect the capacity of the infant to respond to stimulation with less-intense auditory stimulation arousing swaddled infants more effectively than non-swaddled infants. The previous review highlighted “the difference in the physiologic effect of swaddling in QS [quiet sleep] and AS [active sleep]” as an avenue requiring more research (1: e1106). Nelson (2) also conducted a systematic review of swaddling to inform nursing practice, however this did not examine effects on infant sleep and arousal. In their meta-analysis, Pease et al. (3) found evidence to suggest risk of SIDS (a subset of SUDI) increases with infant age when infants are swaddled. They identified a twofold risk for infants aged >6 months. However, their review was limited to “SIDS” as an outcome measure, with no measure of sleep and/or arousal processes. The present review sought to fill these knowledge deficits by answering the question, what is the effect of swaddling on infant sleep and arousal? In developing the literature search strategy, we used the PICO framework to ensure comprehensive and bias-free searches