Tongue movement and intra-oral vacuum of term infants during breastfeeding and feeding from an experimental teat that released milk under vacuum only

Abstract

BackgroundRecent literature supports the theory that vacuum is integral to the removal of milk from the breast rather than peristaltic compression of the breast. AimWe aimed to determine if breastfed infants could remove breast milk from an experimental teat designed to release milk only when a vacuum is applied. MethodsSubmental ultrasound images and intra-oral vacuum measurements were recorded simultaneously during both a breastfeed and a feed with the experimental teat. ResultsInfants placed the nipple and teat a similar distance from the nipple hard–soft palate junction when the tongue was lowered (4.7mm vs 5.3mm). As the tongue lowered the nipple and teat expanded evenly although the nipple expanded more than the teat (3.1mm vs 1.5mm). Both baseline (−31mm Hg vs −12mm Hg) and peak vacuum (−122mm Hg vs −67mm Hg) applied to the breast were significantly higher than for the teat. ConclusionBreastfed infants are able to remove milk from a teat using only vacuum with a similar tongue movement to that of breastfeeding. This evidence supports the theory that vacuum is a critical factor in the removal of milk from the breast.