Vasectomy: what it involves, risks, recovery and reversal

The tubes that carry sperm from each testicle towards the penis, the vas deferens, are cut, blocked or sealed with heat. Sperm can no longer join the semen, so a partner's egg cannot be fertilised. NHS information adapted by NHS 111 Wales says the body continues to make sperm, which are absorbed harmlessly.

Patient.info makes the same point from a practical angle: a vasectomy does not reduce the amount of semen. Sperm contribute only a tiny part, because semen is made mostly in the seminal vesicles and prostate, so ejaculation looks and feels the same.

There are two main approaches. In a conventional vasectomy the scrotum is numbed, small cuts are made at each side, a short section of each tube is removed and the ends are closed by tying or heat, then stitched with dissolvable stitches that go within about a week. In a no-scalpel vasectomy a tiny puncture is made instead of cuts, with little bleeding and no stitches, and it is thought to be less painful and less likely to cause complications. Your doctor will talk through which suits you.

Most operations are done awake under local anaesthetic, and a general anaesthetic is rare. You normally go home the same day.

Some discomfort, swelling and bruising of the scrotum for a few days is common, and paracetamol helps. Blood in the semen for the first few ejaculations is also common and harmless. NHS information advises supportive tight-fitting underwear day and night for the first few days, changed daily, and gentle drying of the area after a bath or shower.

You can usually return to work after 1 or 2 days, but should avoid sport and heavy lifting for at least a week, and sexual activity for at least 7 days. Patient.info suggests heavy lifting or strenuous exercise be avoided for about four weeks, so it is sensible to ask your own provider for its instructions. See a GP if pain persists after painkillers or symptoms continue after a few days.

A vasectomy does not work at once, because sperm remain in the tubes leading to the penis. The NHS information says to use contraception for at least 8 to 12 weeks, and that up to 2 semen tests are done to check that all sperm have gone. Patient.info gives about 12 weeks. The test also identifies the rare cases in which the tubes naturally rejoin, in which case your doctor will discuss options.

Do not stop other contraception until you have been told the result is clear. It is the single most common reason for avoidable failure.

The NHS information lists the possible complications: a collection of blood inside the scrotum (haematoma), hard lumps called sperm granulomas caused by sperm leaking from the tubes, infection, and long-term testicular pain that may need further surgery. Late rejoining of the tubes is very rare.

Cancer is a common worry. The NHS information says prostate and testicular cancer can occur in men who have had a vasectomy but that there is not enough evidence to be sure whether a vasectomy raises prostate cancer risk. Patient.info reports a possible small increase in prostate cancer found in a UK study, from 16 in 1,000 to 19 in 1,000 men, without an increase in deaths from prostate cancer, and notes it is unclear why this might occur.

You should only have a vasectomy if you are sure you want no more children, or none at all. You do not need a partner's legal consent, although discussing it is wise. A GP can refuse to refer if they do not think it is in your best interests, and surgeons may be reluctant if you are under 30. Patient.info notes that some men regret the decision, especially when circumstances change, and it points out that reversible long-acting contraception for women exists and is worth considering as a couple.

Reversal is possible but not guaranteed. NHS Wales information gives a success rate of about 55% if reversal is within 10 years and 25% after more than 10 years, and warns that even a technically successful reversal may not lead to pregnancy. Patient.info quotes private providers as stating around 75% for pregnancy within 3 years. These figures come from different sources and settings, so treat them as indicative. IVF using sperm retrieved from the testicles is an alternative, and it is not always successful, may not be available on the NHS and can be costly.

In most parts of the UK a vasectomy is available free on the NHS, although the NHS information says waiting lists can be several months. A GP, contraception clinic or sexual health clinic can explain local arrangements. Some men choose to pay privately to be seen sooner; you can request a male doctor, but that may lengthen waiting.

Whichever route you choose, expect a counselling conversation, a consent discussion and clear written aftercare. Ask who will arrange your semen test, how results are communicated and what happens if the first sample still contains sperm.