Paper detail

Surface accumulation of spermatozoa: a fluid dynamic phenomenon

Recent mathematical fluid dynamics models have shed light into an outstanding problem in reproductive biology: why do spermatozoa cells show a 'preference' for swimming near to surfaces? In this paper we review quantitative approaches to the problem, originating with the classic paper of Lord Rothschild in 1963. A recent 'boundary integral/slender body theory' mathematical model for the fluid dynamics is described, and we discuss how it gives insight into the mechanisms that may be responsible for the surface accumulation behaviour. We use the simulation model to explore these mechanisms in more detail, and discuss whether simplified models can capture the behaviour of sperm cells. The far-field decay of the fluid flow around the cell is calculated, and compared with a stresslet model. Finally we present some new findings showing how, despite having a relatively small hydrodynamic drag, the sperm cell 'head' has very significant effects on surface accumulation and trajectory.