from the BBC:
Male 'contraceptive jab' closer
Monthly injections of testosterone lowered sperm count
A male contraceptive jab could be as effective at preventing pregnancies as the female pill or condoms, work shows.
The monthly testosterone injection works by temporarily blocking sperm production and could revolutionise birth control, experts believe.
In trials in China only one man in 100 fathered a child while on the injections, the Journal of Clinical Endocrinology & Metabolism reports.
Six months after stopping the jabs the men's sperm counts returned to normal.
Family planning campaigners welcomed the news and said they hoped an injection would give couples more choice and enable men to take a greater share of the responsibility for contraception.
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