RESEARCHERS have developed a mathematical formula based on the movement of a sperm’s head and tail, which significantly reduces the complexities of understanding and predicting how sperm fertilise an egg.

Staff at the Universities of York, Birmingham, Oxford and Kyoto University, Japan, 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.

The team 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.

By analysing the head and tail movements of the sperm, researchers know it moves the fluid in a coordinated rhythmic way, which can be captured to form a relatively simple mathematical formula. This means complex and expensive computer simulations are no longer needed to understand how the fluid moves as the sperm swim.

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.