Male sterilization (vasectomy)

Sterilization

Permanent contraception to block or cut the vas deferens tubes that carry sperm from the testicles

How it works: 
Keeps sperm out of ejaculated semen
Effectiveness to prevent pregnancy: 
>99% after 3 months semen evaluation. 97–98% with no semen evaluation
Comments: 
3 months delay in taking effect while stored sperm is still present; does not affect male sexual performance; voluntary and informed choice is essential.