NNS stands for Non Nutritive Sucking. Any sucking that does not involve the introduction of fluid is considered non-nutritive, as opposed to nutritive sucking, which involves the introduction of fluid and the development of a bolus in the throat and mouth. Non-nutritive sucking is used to start the flow of milk during nursing and has a higher sucking pressure and shorter sucking frequency than nutritive sucking. Non-nutritive sucking is indeed a self-soothing behaviour that has been demonstrated to shorten hospital stays for premature newborns. The fundamental behaviour of a newborn child is non-nutritive sucking (NNS), which is also one of the fetus’s earliest coordinated muscle actions.
Non-nutritive sucking serves a variety of purposes, including state regulation, fulfilling a preterm infant’s desire to sucking while in the newborn critical care unit, and exploration. When done correctly, non-nutritive sucking can help the suck-swallow reflex mature. Although swallowing and sucking action can be noticed as early as 28 weeks of pregnancy, perfect coordination of these actions doesn’t happen until 32 to 34 weeks. In general, preterm newborns develop a synchronised rhythm of sucking, swallowing, and breathing at 32 weeks, allowing for the gradual introduction of nutritive sucking once infants have reached this developmental stage and exhibit sucking cues.