Our observations of
reduced fever at 1 month and
reduced stuffy nose at 6 months associated with nonprone sleep positions are consistent with this hypothesis, as is the reported observation that adults with upper respiratory tract infections have lower nasal bacterial counts after lying supine for 1 hour vs lying prone for 1 hour.11 Also, infants sleeping supine swallow more frequently than infants sleeping prone in response to a pharyngeal
fluid stimulus, suggesting more effective clearing of nasopharyngeal secretions in the supine position and, hence, less potential for eustachian tube obstruction and fewer
ear infections.12