Prof. David Elad

Infant breastfeeding

Breastfeeding is strongly encouraged by societies and communities because breast milk provides nutrients and immunities required for growth and development during the first months after birth. In addition, during breastfeeding the infant is exercising his/her oro-facial muscles for future tasks of speaking and chewing, and also have higher oxygen saturation than bottle-fed infants. The process of breastfeeding requires dynamic synchronization between oscillation of the infant's mandible, rhythmic motility of the tongue, and the breast milk ejection reflex that drives maternal milk towards the nipple outlet. First, the infant latches on to the breast and nipple so that the nipple, areola and underlying mammary tissue and lactiferous ducts are drawn into the infant’s mouth with the nipple tip extended as far as the hard-soft palate junction (HSPJ). Then, the infant moves its mandible up and down, compressing the nipple-areola complex and the underlying lactiferous ducts with its gums in a suckling process that extracts the milk into its mouth. Simultaneous with compression, spontaneous undulating motions of the infant tongue channel the milk posteriorly and trigger the swallowing reflex. During breastfeeding, suckling, swallowing and breathing are coordinated by the central nervous system in a way that allows for the infant's continuous feeding without breathing interruptions. The following physical mechanisms were proposed to explain how the infant extracts milk from the breast: (i) sucking – emptying of the nipple-breast contents by development of sub-atmospheric pressures within the infant oral cavity and (ii) mouthing – squeezing out of the nipple-areola contents by compression between the jaws or other mouth parts. We have explored the physical aspects of infant feeding via noninvasive visualizations of the moving components in the oral cavity and a biophysical model.