Fertility, pregnancy and breast cancer treatment

1. Will breast cancer treatment affect my fertility?
2. Referral to a fertility clinic
3. Fertility in women
4. How breast cancer treatments can affect fertility
5. Options for preserving fertility
6. Contraception during and after breast cancer treatment
7. Deciding if you want fertility preservation
8. Planning pregnancy after breast cancer treatment
9. Breast cancer during pregnancy

1. Will breast cancer treatment affect my fertility?

Some treatments for breast cancer, such as chemotherapy, can affect your ability to become pregnant.

Having breast cancer treatment may mean you have to think about your fertility sooner than you had planned. While your main concern is probably treating your breast cancer, if having children of your own is important to you then procedures to preserve your fertility – such as IVF or freezing eggs – can be offered.  

It’s important to talk to your specialist team about this before your breast cancer treatment begins.

You may also want to download or order our booklet Fertility and breast cancer treatment

Back to top


2. Referral to a fertility clinic

Your specialist team should offer you a referral to a fertility specialist to discuss the option of preserving your fertility, if having children in the future is important to you.

Find out what happens at a fertility clinic »

Jackie talks about the importance of being referred to a fertility specialist.

Questions to ask

Take time to think about questions you may want to ask to get the information you need. If you have a partner, it’s helpful to include them in this discussion.

Questions you might want to ask your specialist team or fertility clinic include:

  • Can I check if I’m fertile before treatment starts?
  • How will my age affect my fertility?
  • What are my chances of getting pregnant after treatment?
  • How long after treatment will I have to wait to find out if I’m still fertile?
  • How can I keep my fertility?
  • Will having treatment to preserve my fertility delay my cancer treatment?
  • Will I be able to have fertility treatment on the NHS (including embryo or egg storage)? If not, how much will it cost?
  • What does fertility treatment involve?
  • How successful are the different methods of preserving fertility?
  • Is it safe for me to have fertility drugs?
  • If I don’t have a partner, can I use a sperm donor?
  • Would a future pregnancy affect the chances of cancer coming back?
  • Could my cancer treatment affect the health of any children I might have in the future?
  • Assuming I can still have children, how long after treatment should I wait?

If you want to see a fertility specialist and this hasn’t been offered, ask your specialist or breast care nurse as soon as possible after your diagnosis to reduce any possible delays to your treatment. You can ask to be referred to a fertility clinic that has experience in helping women having cancer treatment.

For a list of fertility clinics in the UK, see the Human Fertilisation and Embryology Authority (HFEA) website.

NICE guidelines

NICE (National Institute for Health and Care Excellence) guidelines for assessing and treating people with fertility issues recommend that women with breast cancer should:

  • have the chance to discuss the impact of cancer and its treatment on future fertility with their cancer team at the time of diagnosis
  • be offered appropriate procedures to preserve fertility if their breast cancer treatment may lead to infertility, as long as they’re well enough to have the procedures, this won’t worsen their condition and there’s enough time before cancer treatment begins.

The usual conditions for deciding whether someone can have fertility treatment shouldn’t apply to people with cancer.

NICE guidance only applies to England. Assessment and treatment may be different in Wales, Scotland or Northern Ireland and your specialist team can tell you more about this.

  • If you’re not offered a discussion about fertility preservation with a fertility specialist, you can talk to your GP (local doctor).
  • If you’re still not happy, you can make a complaint to your local Clinical Commissioning Group (find your local CCG on the NHS website).
  • If you’re unhappy with the decision from the CCG, you can complain to the independent Parliamentary and Health Service Ombudsman.

Back to top


3. Fertility in women

To understand how breast cancer treatments can affect fertility, it can be useful to know some basic facts about fertility in women.

Women are born with a set number of eggs in their ovaries (you don’t produce new ones). By the time a woman reaches puberty, the number of eggs she has will have already decreased, and the number continues to decrease as she gets older. Generally, the quality of the eggs also reduces as a woman ages, which can affect fertility.

Every month, a woman’s ovaries release at least one egg. Pregnancy occurs if an egg is fertilised by a man’s sperm and implants itself in the womb. If an egg is not fertilised, you have a period.

graph showing fertility decline

The ovaries stop releasing eggs, and monthly periods stop, when a woman reaches the menopause (around the age of 51).

Back to top


4. How breast cancer treatments can affect fertility

Can chemotherapy cause infertility?

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.

The likelihood of becoming infertile depends on the type of drugs used, the dose given, your age and your current fertility. You can usually take time to consider your options for preserving fertility before starting treatment. If you want to have children in the future, discuss this with your breast cancer team.

The chemotherapy drugs most likely to cause infertility are a group called ‘alkylating agents’. One of these (cyclophosphamide) is commonly used in combination with other chemotherapy drugs to treat breast cancer.

The effect of some other chemotherapy drugs, such as taxanes (docetaxel and paclitaxel), on fertility hasn’t been as widely studied, but evidence suggests they’ll also have a negative effect on fertility.

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, so it’s important to speak to your specialist team if you have any concerns.

Laura discusses the decisions she made around her fertility.

Can you become pregnant while taking tamoxifen?

Hormone treatments are used in women whose breast cancer is oestrogen receptor positive (ER+). This means the breast cancer has receptors within the cells that bind to the female hormone oestrogen and stimulate the cancer to grow.

Some of the most commonly used hormone drugs for pre-menopausal women with breast cancer are:

In most pre-menopausal women who take tamoxifen, the ovaries continue to work. When you start taking tamoxifen it may stimulate ovulation (release of the egg from the ovary) making you more fertile.

For some women, continued use of tamoxifen means periods become less regular, lighter or disappear altogether. Generally, your periods will start again once you stop taking tamoxifen, as long as you haven’t gone through the menopause naturally while taking the drug. However, it may take four to five months for your cycle to become regular again.

Goserelin works by switching off the production of oestrogen from the ovaries. It is often combined with other hormone therapies used to treat breast cancer, such as tamoxifen or aromatase inhibitors. Aromatase inhibitors are normally only recommended for post-menopausal women but can be given to pre-menopausal women alongside goserelin.

Hormone treatment is usually taken for five years or longer. While you’re taking hormone treatment you will be advised not to get pregnant as it may harm a developing baby. Even if your periods stop while you are taking hormone treatment you could still get pregnant.

Because of the length of time it’s taken for, the side effects of hormone treatment may hide the signs of a natural menopause. It may only be when you finish taking it that you realise your menopause has started.

If you want to have children and you’re in your 30s or early 40s, taking hormone treatment for five years or more may be an issue you want to discuss with your specialist team.

A trial called the POSITIVE trial (Pregnancy Outcome and Safety of Interrupting Therapy for Women With Endocrine Responsive Breast Cancer) is looking into the safety of interrupting hormone treatment to try to get pregnant.

Kerry decided to have fertility preservation treatment before starting chemotherapy.

Removal of the ovaries (oophorectomy)

Some women may have their ovaries removed as part of their breast cancer treatment, or as risk-reducing treatment if they have an altered gene. If you have had this operation you will be left infertile, but can consider egg or embryo donation in the future. See our information on surgery to remove the ovaries.

Back to top


5. Options for preserving fertility

Several procedures to preserve your fertility may be available to you before you start your breast cancer treatment.

Find out about your options for preserving fertility »

Back to top


6. Contraception during and after breast cancer treatment

Generally women are advised not to get pregnant while having treatment for breast cancer. This is because treatment for breast cancer can damage an unborn baby at the early stages of development.

If you’re sexually active with a man, it’s important to discuss contraception with your specialist team. They may refer you to a family planning clinic or your GP (local doctor), who can advise you on the most appropriate contraception for you.

Women having treatment for breast cancer (including the hormone treatment tamoxifen) are recommended to use non-hormonal methods of contraception, such as condoms, Femidoms or a diaphragm.

It may also be possible to use a coil (IUD or intrauterine device). However, you would need to discuss this with your specialist as not all types are suitable for women with breast cancer.

The contraceptive pill is less commonly advised after a diagnosis of breast cancer. This is because the hormones in the contraceptive pill could possibly stimulate any remaining breast cancer cells. However, the morning-after pill can be used in emergencies as it’s a single dose of hormones and unlikely to affect your breast cancer. Speak to your specialist team if you have any concerns.

You should use reliable contraception before and throughout your treatment. After treatment your decisions about contraception will depend on how you feel about getting pregnant. Generally, you should assume you could still get pregnant unless you haven’t had a period for at least a year after completing your treatment if you’re 40 or over, or two years if you’re under 40. However, this is a general guide and varies for each person.

Back to top


7. Deciding if you want to have fertility preservation

Before you start your breast cancer treatment you will need to decide if you want to take steps to preserve your fertility, or if you would prefer not to have any fertility treatment.

Some women are very clear about what they want to do, while others have a harder time making a decision. There is no ‘right’ or ‘wrong’ answer – it’s important to choose what’s right for you.

Talking to a fertility specialist and finding out what options are available can help you come to a decision. It might also help to talk everything through with your partner (if you have one), breast cancer team, family and friends.

For more information, read about options to preserve fertility.

A few women may consider declining chemotherapy if they’re concerned about their fertility. Talk to your consultant about the benefit of having chemotherapy or the effects that different chemotherapy combinations may have on your fertility.

Back to top


Last reviewed: April 2017
Next planned review begins 2019

Let us know what you think

Please note that we cannot respond to comments. If you have any questions about breast cancer please contact the Helpline on 0808 800 6000.

Sign up for our newsletter

Related Publication