Mechanics and energetics of nutritive sucking: a functional comparison of commercially available nipples

The purpose of this study was to compare the mechanics of sucking for 48 term infants with four different nipple units: Gerber Newborn (Gerber Products Company, Fremont, Mich.), Playtex (Playtex Products, Westport, Conn.), Evenflo (Evenflo Products Co., Canton, Ga.), and Gerber NUK. At 24 hours after birth, infants were assigned randomly to one of the nipple units and were studied twice with that nipple unit. A customized data acquisition system was used to measure and record the following variables: intraoral suction, sucking frequency, work, power, milk flow, milk volume per suck, and oxygen saturation. Although no statistically significant differences among the nipple units were noted for intraoral suction, sucking frequency, power, and oxygen saturation, the data revealed that the Playtex nipple unit was accompanied by higher peak milk flow and greater volume of milk per suck (p < 0.05). Infants fed differently with the Playtex nipple than they did with the other nipples. Our findings indicate that the Playtex nipple permits a greater milk flow in response to similar amounts of suction, work, and power when compared with others. The mean total work per such was significantly lower in the Gerber NUK group compared with the Playtex group. In addition, the total number of sucks per volume ingested was higher, and the total time to ingest a specific quantity of milk was longer for the Gerber NUK nipple.