DYNAMICS OF HUMAN-MILK EXTRACTION - A COMPARATIVE-STUDY OF BREAST-FEEDING AND BREAST PUMPING

We describe a mathematical model of the flow and deformation in a huma n teat. Our aim is to compare the theoretical milk yield during infant breast feeding with that obtained through the use of a breast pump. I nfants use a peristaltic motion of the tongue, along with some suction , to extract milk, whereas breast pumps use a cyclic pattern of suctio n only. Our model is based on quasi-linear poroelasticity whereby the teat is modelled as a cylindrical porous elastic material saturated wi th fluid. We impose a cyclic axial suction pressure difference across the teat and impose a radial compressive force moving along the teat w hich mimics infant suckling. This is compared to the case of cyclic an d steady pumping only which models the action of breast pumps. The res ults illustrate that there is an optimal time to apply the compressive force during the suction cycle that will increase the flow rate in ou r theoretical teat. The model and results may be of use in the future design of effective breast pumps. (C) 1997 Society for Mathematical Bi ology.