A vasectomy is a surgical procedure that involves blocking the path of sperm by cutting, or tying a man's vas deferens.

This will prevent sperm from becoming part of the ejaculate (semen), and makes the man sterile. Following a vasectomy, sperm are still produced in the testicles but are absorbed by the body. A vasectomy takes about 15-20 minutes and can usually be carried out with a local anaesthetic. Two small cuts are made in the scrotum, then the vas deferens is cut and tied.

  • Blocking of vas deferens (tube that carries the sperm into the semen) to prevent pregnancy
  • Meant to be permanent
  • Safe, effective, contraception should be used for 3 months until absence of sperm in semen is confirmed
  • Day case surgical procedure 

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How effective is a vasectomy?

Vasectomy is not immediately effective because live sperm remain in the vas deferens until they are ejaculated in the semen. After three months a semen analysis must be taken to check that there are no live sperm in the ejaculate. Once this is established, vasectomy is 99.85-99.9% effective. This means that, on average, of 1000 women whose partners have had a vasectomy, only1 of them will become pregnant at some time in the future.

What are the advantages of vasectomy?

  • Highly effective method of contraception
  • Simple, quick and safe operation
  • It does not interfere with sexual intercourse or sexual function (erections)
  • Long-term complications are rare

What are the disadvantages of vasectomy?

  • Temporary discomfort may be experienced following the operation, such as pain, bruising, bleeding, swelling or inflammation
  • Vasectomy is not immediately effective
  • Reversal is not always possible

Are there any long-term consequences of vasectomy?

  • Does not affect the appearance or function of the penis or testicles in any way
  • Erections, orgasms and ejaculations will be the same as before the operation
  • Concern has been raised about testicular and prostate cancer in men who have had a vasectomy. World Health Organisation expert committees have reviewed the research and found no proven association exists between vasectomy and cancer