Cancer treatment and fertility in men

How treatment can affect fertility

Your cancer doctor or nurse will talk to you about your treatment options and possible side effects before you start any cancer treatment.

The main treatments are:

  • drugs (chemotherapy, hormonal therapy and targeted therapy)
  • radiotherapy
  • surgery
  • stem cell transplants.

When you are diagnosed with cancer, it can feel like everything happens very quickly. You may need some time to adjust to what is happening. It can help to talk to family and friends or someone else you trust.

Each treatment can affect fertility in different ways. It is always best to ask your healthcare team for more information. As well as the information here, we have more detailed information about different cancer treatments and fertility for men.

You may feel less interested in sex during cancer treatment. Some treatments can cause side effects that make having sex difficult. This can also affect your chances of making someone pregnant naturally. You can find out more about coping with sexual problems.

Cancer treatment and fertility in men

For men, cancer treatment may:

  • stop or slow down sperm production
  • cause problems with erections or ejaculating.


Some cancer treatments damage the cells that make sperm. This means that you may produce less sperm, or sperm that is not very healthy. Your body may still make semen, so you will still ejaculate (come). But there is less, or no, sperm in the semen and it is less likely to fertilise an egg.

After some types of treatment, the cells that make sperm may recover. But it is difficult to predict exactly when that will happen. Fertility testing is the only way to know if you are producing sperm again.

Remember, just because you have had cancer treatment doesn’t mean that your sperm will definitely be affected. If you are having sex and your partner could get pregnant but you don’t want to have a baby, use contraception.

Erections and ejaculating

Low testosterone

Some cancer treatments reduce your testosterone hormone levels. This can make it difficult to get an erection, and can sometimes make you less interested in having sex. It can also cause other problems such as thinning of the bones (osteoporosis), tiredness and a low mood.

If your testosterone levels don’t recover, you can take testosterone replacement therapy (TRT). You usually take this as injections or a gel or patch on your skin. TRT can help with sex drive and erections, but your body may not be able to make sperm when you are taking it. This means you won’t be able to get someone pregnant while taking it.

You can take TRT for the rest of your life. If you want to have children, it is possible to stop TRT for a while to start a family.

Damage to the nerves and blood supply

Sometimes cancer, or cancer treatment to the pelvic area, can damage the nerves and blood supply to the penis and testicles. Your pelvic area is the area between your hips and below your belly button.

Damage to this area can cause problems with getting an erection or how you ejaculate.

This does not happen very often, but the damage can be permanent. You may still be able to have fertility treatment using your own sperm to have a baby.