Rabbits were among the first "guinea pigs," now research on lab monkeys has also confirmed that a new gel injection works like a vasectomy, yet could be reversed without surgery.
It works by injecting the gel into the vas deferens, the tube down which sperm travels.
The gel's sponge-like texture blocks sperm, yet allows lighter fluids to pass.
Researchers say the gel proved to be successful for long-term contraception for the monkeys.
They posted their findings in the journal Basic and Clinical Andrology, noting a few complications, all of which were similar to those associated with a vasectomy.
Previous trials on rabbits proved the new male contraceptive gel lasted a full year and was reversible by injecting more fluid to flush out the gel.
Human trials are in the works and, if successful, the gel could be available for purchase as early as next year.
Other forms of male contraception are also being researched, including a non-hormonal daily pill which prevents sperm from swimming, as well as a separate drug which made the sperm of mice unable to fertilize an egg.