This work aims to present a quantitative metric to assess the impact of feeding teats on the nutritive sucking of newborns. Two different teat models are compared: a classical model (model C), and a model provided with two opposite recesses to match the anatomical characteristics of the mouth of a newborn (model I). This latter feeding teat model has been specifically designed to promote the attachment of the baby, thus improving her/his nutritive sucking performance.Feeding teats are instrumented with a device to assess nutritive sucking (the Feeding Assessment Monitor, FAM). The device records feeding pressures and a software extracts quantitative features already used and validated in clinical applications.Comparative cross-over analysis on 30 healthy newborns, demonstrates the appropriateness of the proposed metric to reveal differences in the teat models. In particular, our data confirm the better attachment of newborns when fed with the I model: they show a longer feeding, with higher level of depressurization, higher regularity, and higher number of sucking events.