British and Japanese researchers have developed a mathematical formula based on the rhythmic movement of a sperm’s head and tail which contributes in the understanding how sperm makes the journey towards fertilising an egg.

Researchers from York and Kyoto universities found that the sperm’s tail creates a characteristic rhythm that pushes the sperm forward, but also pulls the head backwards and sideways in a coordinated fashion.

Successful fertility relies, among other factors, on sperm’s motility.

The researchers aim to use these new findings to understand how larger groups of sperm behave and interact. The work could provide new insights into treating male infertility.

The research demonstrated that the sperm has to make multiple contradictory movements, such as moving backwards, in order to propel it forward towards the egg.

The whip-like tail of the sperm has a particular rhythm that pulls the head backwards and sideways to create a jerky fluid flow, countering some of the intense friction that is created due to their diminutive sizes.

Dr Hermes Gadêlha, from the University of York’s Department of Mathematics said: “Measurements of the beat of the sperm’s tail are fed into a computer model, which then helps to understand the fluid flow patterns that result from this movement. Numerical simulations are used to identify the flow around the sperm, but as the structures of the fluid are so complex, the data is particularly challenging to understand and use”.

The researchers hope that this mathematical formula will make it easier to predict how large numbers of sperm swim and understand better why some sperm succeed and others fail.
Read more: https://www.york.ac.uk/news-and-events/news/2017/research/how-sperm-swim-revealed-in-maths-formula/

Image credit: https://www.york.ac.uk/news-and-events/news/2017/research/how-sperm-swim-revealed-in-maths-formula/