Non-nutritive sucking habits in sleeping infants

Pacifier use has been postulated to decrease the risk of sudden infant death syndrome (SIDS). The responsible mechanisms are, however, unclear.

Since little is known about the non-nutritive sucking (NNS) habits of infants during sleep, we investigated NNS patterns and changes of physiological parameters during NNS in sleeping infants.

Polygraphic recordings were performed in 12 infants with a median age of 55 days (range 7-82) who regularly used a pacifier during sleep. Episodes of active suckling (bursts) and quiescent periods were differentiated by video observations. We evaluated the time of suckling in relation to the total time of pacifier use, the median number of bursts per min, the median duration of single bursts and the median interval between 2 sequent bursts. In 48 randomly selected bursts, we additionally analyzed changes in heart rate, respiratory frequency and oxygen saturation compared to the 10-second period preceding the burst.

Median sleep time with a pacifier held in mouth was 31.3 min (13.0-117.6), of which 15.5% (6.4-36.7%) was spent with active suckling. The median number of bursts per min was 2.2 (1.2-4.5). The median duration of a burst was 3 s (1-22) and the median interval between 2 bursts was 10 s (1-1,434). Heart rate, respiratory frequency and oxygen saturation did not change significantly during suckling bursts.

This pilot study presents important data for sucking habits in pacifier users which may provide a basis for further investigations concerning the efficacy of pacifiers in SIDS prophylaxis.