One of the challenges in examining development of newborns is measuring activities which are correlated to their health. Oral feeding is the most important factor in an infant's healthy development. Here, we present a new device that can measure intraoral and expression pressures produced in a newborn's mouth by non-nutritive sucking. We then develop a method to extract time-intervals that a sucking has occurred. To show an application of this device, we use Apgar score as a reference of the general health of newborns, and we evaluate these scores with the non-nutritive sucking patterns demonstrated by the infants. We show that for the pairs of infant with the same background but different Apgar scores, those with lower Apgar scores have lower pressure amplitudes while sucking. Importance of non-nutritive sucking skills in the development of newborns and ease of using our device make it useful for clinical studies of infantile health.