But researchers of male birth control in the United States say they have to kindly disagree with the notion that the effects of abuse rule out any future for testosterone as birth control.
"I'm not sure I agree that it can lead to sterility," said Armory, who added that in the 35 male hormonal-contraception studies using testosterone he has seen, there has never been a case of irreversible sterility.
"There are these reports of sterility in bodybuilders who take hormones that we don't use; those are veterinary hormones," Armory said. "We have ongoing studies using hormones and, if the subjects were at risk for sterility, we wouldn't be able to do the study."
Armory, who recently started a birth control study with testosterone gel, said researchers are largely experimenting with the timing and application of testosterone at this point.
Would Male Birth Control Ever Work?
Dr. Ronald Swerdloff, a veteran male contraceptive researcher, believes there are issues other than safety or effectiveness that are keeping male hormone contraception research from reaching its goal.
"This as been known for 15 and 20 years that [testosterone injections] are quite effective and that there is a limitation that it didn't work on everybody," Swerdloff said.
"But there's another problem and the other problem is that it doesn't work right away," he said.
Unlike the condom, which works immediately, or the pill which works within one month's cycle, a man on testosterone may have to wait three months before sperm production shuts down.
Swerdloff thinks the lack of interest by pharmaceutical companies may be another contributor to barriers for male hormone contraception research.
"There hasn't been success in finding a pharmaceutical company that wants to take on this approach," Swerdloff said. "The reasons for that, in my opinion, are the same reasons that in general there have been very, very few new contraceptions for men, or even for women."
Swerdloff believes that -- unlike a new cancer drug that people need and would pay big money for -- pharmaceutical companies don't see the profits in male contraception investments when healthy people already have relatively cheap, safe options for women's birth control or other methods.
"There would be a considerable up-front cost," Swerdloff said.
But at least all doctors can agree that one thing male contraception research isn't missing is interest by the public.
"We don't have a lot of trouble recruiting men for our studies," Amory said. "There are many couples where the woman can't use the pill for a variety of reasons, or just doesn't want the pill."
Amory believes the challenges with male contraception are much greater.
"It's a lot easier to suppress the production of one egg every month than the 1,000 sperm men make once a second, everyday," he said.
"Even when they're lying on the couch, men are actually doing something."