Does breast cancer treatments affect fertility?

Breast cancer is the most common cancer in women and the second most common cancer overall. There were over 2 million new cases in 2018.

Many women are able to become pregnant after breast cancer treatment. However, some treatments can make it harder to get pregnant.

If you want to have children, some doctors advise breast cancer survivors to wait at least 2 years after all treatment has finished before trying to get pregnant. Keep in mind that this advice is not based on data from any clinical trials. And some breast cancers can come back after the 2-year mark, so every case is different.

Chemotherapy can cause infertility in women who haven’t been through the menopause (pre-menopausal). It can affect the functioning of the ovaries, reducing the number and/or quality of eggs.

Chemotherapy can also cause your periods to stop (amenorrhoea). This may be temporary or permanent. In general, the younger you are when having treatment, and particularly if you’re under 35, the more likely it is that your periods will return. Women over 35 are more likely to lose their fertility after chemotherapy.

It’s possible to stop having periods temporarily during treatment and to start having them again later, months or occasionally even a few years after treatment has finished.

Even if your periods return after chemotherapy, the menopause is likely to happen sooner (up to 5–10 years earlier) than it would have done if you hadn’t had chemotherapy. This may mean you have a shorter time than normal to try to get pregnant.

If your periods do return, it doesn’t necessarily mean your fertility has been unaffected, the likelihood of becoming infertile depends on the type of drugs used, the dose given, your age and your current fertility.

If you think you may want to have children one day, or just want to keep your options open, the best time to talk to your doctor about fertility is before you begin breast cancer treatment. This way you will give you the option to preserve your fertility through eggs freezing in order to do IVF after completion of chemotherapy. Egg Freezing offers you flexibility in delaying pregnancy for later in life and allows you to take control of your own biological clock.