(male sterilisation) is a surgical procedure to cut or seal the tubes that carry a man's sperm to permanently prevent pregnancy.
It's usually carried out under local anaesthetic, where you're awake but don't feel any pain, and takes about 15 minutes.
In rare cases, you may have a general anaesthetic, where you're asleep during the operation.
At a glance: facts about vasectomy
A vasectomy is more than 99% effective.
It's considered permanent, so once it's done you don't have to think about contraception again.
It doesn't affect your sex drive or ability to enjoy sex. You'll still have erections and ejaculate, but your semen won't contain sperm.
You'll need to use contraception for at least 8 to 12 weeks after the operation, because sperm will still be in the tubes leading to the penis.
Up to 2 semen tests are done after the operation to make sure that all the sperm have gone.
Your ball sack (scrotum
) may become bruised, swollen or painful – some men have ongoing pain in their testicles.
As with any surgery
, there's a small risk of infection.
It's very difficult to reverse, so be sure it's right for you.
A vasectomy doesn't protect against sexually transmitted infections (STIs
), so you may need to use condoms as well.