Radiotherapy can sometimes cause physical changes that may affect your sexuality. If you are having problems, it may help to talk these over with your partner and the radiotherapy staff. Although it can be embarrassing to talk to the hospital staff about such intimate things, remember that they are used to dealing with these issues and can suggest things that will help you. You can also get advice and support from the British Association of Sexual and Relationship Therapy. You may also wish to phone our cancer support service and speak in confidence to one of our cancer nurse specialists.

External and internal radiotherapy to the pelvis usually affects the ovaries. Radiotherapy to the ovaries will cause the menopause. This may happen gradually over a few months. The normal signs of the menopause will develop, such as hot flushes, dry skin and dryness in the vagina. This can be very distressing, particularly for younger women who are not prepared for the menopause. Depending on your type of tumour, your doctor may prescribe hormone replacement therapy, which can help to overcome these problems. Occasionally – for example, when treating some types of cancer called lymphomas – the ovaries may be moved out of the treatment area and into the upper part of the abdomen. This is done by an operation before the radiotherapy treatment.

Radiotherapy to the vaginal area can occasionally make the vagina become narrower. The radiotherapy staff will show you how to use vaginal dilators and a lubricant to keep your vagina supple once you have finished treatment.

At first you may find sex uncomfortable, and it may be helpful to use a lubricant such as KY Jelly®, which you can buy at your local chemist. Regular sex may help to prevent narrowing of the vagina, but many women will not feel ready to return to a regular sex life while they have the side effects of radiotherapy. This is very natural; your interest in sex will usually come back as the effects of the treatment wear off. In the meantime, using a dilator is an effective way of keeping your vagina healthy.

Our section on sexuality and cancer offers useful information.

Men who have radiotherapy may have some problems with sex. It may be that you lose interest in sex or become temporarily unable to have an erection (impotent) because of your anxiety about your illness, or worries about the future, or because the treatment is making you too tired to think about sex. These effects may last for a few weeks after radiotherapy has finished, and can be very distressing.

Talking openly to your partner about your problems may help, and you can ask the radiotherapy staff about any problems that you have. Radiotherapy to the pelvis, for example, to treat bladder, rectal or prostate cancer, may cause impotence, which may develop months or years after your radiotherapy is finished. There are practical ways to overcome impotence and these are discussed in detail in our section on sexuality and cancer.

It is very important for women of childbearing age to use effective contraception throughout their radiotherapy treatment. Radiotherapy could cause a miscarriage or cause a child to be born with abnormalities. If you think that you may be pregnant when you are told that you are to have radiotherapy treatment, it is extremely important to let your clinical oncologist know. The oncologist will discuss with you whether the treatment can be delayed until the baby is born.