Researchers across the world are trying to develop a male version that suppresses the production of sperm. This group in Australia says it's succeeding. 55 couples took part in the trial with the hormone called Progesterone...injected once every three months to stop sperm production. None became pregnant.
Nicole Heyns, Trial Participant we have two children and a dog and this was going to be a full proof way of guaranteeing we wouldn't have children while we were on the trial.
The hormone does stop sperm production, and it also suppresses the man's sex drive. So every four months these pellets of testosterone were implanted under the man's skin to restore libido. It worked for some men, but not others who simply rejected the pellets.
Professor David Handelsman, Anzac Rsearch Institute I think in the near future what will be possible is that a combination injection would work very well.
Other researchers have developed a male pill to be taken daily. Whether it's a pill or an injection, would women trust men to take it?