A non-hormonal, reversible and non-toxic male birth control could be a step closer, with scientists successfully targeting a protein that's crucial in making fertile sperm. Knocking this protein out for a period of time would give men control over their protection window, much like oral…
Safe, cheap, permanent but trivially reversible male birth control was invented in 1979 and has yet to be approved for US sale.
Can you share more info?
RISUG is a technique by which a polymer with specific electrical properties is injected into the vas deferens. This polymer messes up the flagella on sperm that pass nearby. Since “nearby” is a distance larger than the radius of the vas deferens, this means all sperm passing through get their flagellum screwed up, can no longer swim, and is therefore immotile.
It makes the man essentially sterile, until he wants to reverse the effect at which point a second injection simply washes the original polymer layer off the inner lining.
Probably talking about RISUG, although the US equivalent is Vasagel.
Basically Vasagel plugs up the Vas Deferens so sperm can’t get out, and RISUG rips sperm to shreds as they come out. It lasts for 10 years, and is reversible with a shot of baking soda.
RISUG is approved in India (where it was developed), and Vasagel is being developed by a foundation instead of a pharmaceutical company, so progress has been slow.