INFO:

When thinking about future contraceptive options for men, rather than stopping the production of sperm or blocking its pathway, what if we could step in at the end of its journey and impede its ability to fertilise the egg? Promising research along these lines is looking at ways to stop sperm going into a special state called ‘hyperactivation’, where it lashes its tail about wildly. This video shows what sperm looks like in various states, including hyperactivation. (No audio)