For men who resent wearing condoms, a new non-intrusive solution is on the anvil - a birth control pill.
At least two projects are in the pipeline for choking male fertility.
One is H2-gamendazole that makes sperms go half-cooked. Normally, premature sperm cells grow a tail and head in the testis, but H2-gamendazole keeps them from reaching this stage of development.
"If there's no sperm, the egg's not going to get fertilised," said Joseph Tash, a reproductive biologist at the University of Kansas' Medical Centre in the US.
Tash has worked on the compound since 2001.
The other potential compound is JQ1 that can trick the body into forgetting how to make sperm!
JQ1 was found blocking bromodomain proteins in cancer cells by Jay Bradner and his team at Harvard's Dana-Farber Cancer Institute. The uncontrolled division of the abnormal cells ceased due to it.
JQ1 also obstructed a testicle-specific bromodomain called BRDT, making the sex cells that would otherwise produce sperms draw a blank about their own behaviour.
Mice treated with JQ1 can copulate with abandon yet produce zero offsprings.
But it will be several years before the drug is available.
Researchers would have to find a version of the molecule that works on the testicle protein without coming up with any side effects.
