Possible effects on fertility

Unfortunately, some chemotherapy drugs can cause infertility. Infertility is the inability to become pregnant or to father a child. This may be temporary or permanent, depending on the treatment that you have.

It’s important to discuss your infertility risk with your cancer doctor before you start chemotherapy. If you have a partner, it’s a good idea to include them at this discussion.

Although chemotherapy can affect fertility, it’s still possible for a woman to get pregnant or for a man to get his partner pregnant during chemotherapy. It’s important to avoid pregnancy when you’re having chemotherapy as the drugs could harm a developing baby.


Some, but not all, chemotherapy drugs may temporarily or permanently stop your ovaries producing eggs.

Chemotherapy may cause your periods to become irregular or stop for a while (temporary infertility). But after treatment stops the ovaries can start producing eggs again and your periods will return to normal. It may take a few months or up to two years for them to come back again. The younger you are, the more likely you are to have periods again and still be fertile after chemotherapy.

If your periods don’t come back you won’t be able to become pregnant and will have your menopause.

It’s important to know if your fertility is likely to be affected before chemotherapy starts. You can then decide if you want to be referred to a fertility specialist. They can discuss possible options to help preserve your fertility, such as storing embryos (fertilised eggs) or eggs, with you.


Some chemotherapy drugs have no effect on fertility, but others can slow down or stop you producing sperm. For most men this will be temporary. Any problems with sperm production won’t stop you from getting an erection or enjoying sex.

Even if your chances of becoming infertile are low, you may still be advised to store sperm for use in the future. This has to be done before you start chemotherapy. Teenage boys at risk of infertility should also, if possible, have their sperm stored for later years.

You’ll usually be asked to produce several sperm samples over one or two weeks. These will be frozen and stored so they can be used later to try to fertilise an egg and make your partner pregnant.

It can take a few years for your sperm count to go back to normal after chemotherapy. Unfortunately in some men infertility is permanent. Your doctor can check your sperm count after treatment is over.

Feelings about infertility

If you had been planning to have children, infertility can be very hard to come to terms with.

You may find it helpful to talk about your feelings with a trained counsellor or therapist who specialises in fertility problems. Your doctor or specialist nurse may be able to arrange. Our cancer support specialists on freephone 0808 808 00 00 can also provide support.

Back to Side effects of chemotherapy

Possible side effects

There are many possible side effects to chemotherapy treatment, but they can be reduced. There are practical ways to manage them.

Chemo brain

Chemo brain describes changes in memory, concentration and the ability to think clearly. These changes can sometimes happen during or after cancer treatment.