This prevents the passage of sperm into the penis. It takes about three months or up to 20 ejaculations for all the sperm to be removed from the reproductive system, so couples will need to use another form of birth control for some time after the procedure. Two months after the vasectomy, doctors perform a sperm analysis to make sure there are no sperm in the semen. The failure rate for vasectomy is about one percent, and is usually caused by couples having unprotected sex before all the sperm have left the reproductive tract. On rare occasions, vasectomy failure can be caused when the doctor cuts the wrong structures or the severed ends of the vas deferens rejoin.
Women choosing permanent sterilization can have a tubal ligation.
A tubal ligation is a much more involved procedure than a vasectomy. Failure rates for tubal ligation are about two percent - slightly higher than those for vasectomy. Since only one partner needs to be sterilized to prevent pregnancy, couples need to choose which partner will have the procedure. It s a very personal decision. Many men are reluctant to have a vasectomy, even though it has no effect on sexual performance.