Contact our breast care nurses 0808 800 6000

Breastfeeding and breast cancer treatment

Find out more about breastfeeding and breast cancer treatment, including chemotherapy and breastfeeding.

1. Can I breastfeed during or after treatment?

If you were diagnosed with breast cancer during or soon after pregnancy, your treatment team and midwife will give you advice about breastfeeding. 

The advice will usually depend on where you are in your treatment plan.  

If you were breastfeeding when you were diagnosed with breast cancer, your treatment team will recommend you stop breastfeeding.

If you have questions about breastfeeding, talk to your treatment team and other breastfeeding experts such as your midwife for support and advice. 

2. Breastfeeding after surgery

Breastfeeding may be possible for some women diagnosed during pregnancy after breast surgery, but not while having , , hormone or targeted therapy. 

Breastfeeding is most successful from the other, non-treated breast. 

3. Chemotherapy and breastfeeding

You’ll be advised not to breastfeed during and for some time after chemotherapy. 

This is because the chemotherapy drugs can pass to your baby through the breast milk. 

If you're towards the end of your chemotherapy you may want to express milk. You will not be able to use this milk to feed your baby. But expressing milk means you’ll still be able to produce milk to breastfeed your baby after you finish chemotherapy.

4. Radiotherapy and breastfeeding

Although many women can produce milk from the treated breast, the amount of milk is often reduced. 

Breastfeeding from a breast that has been exposed to radiotherapy can cause an infection (mastitis), which can be difficult to treat.

Breastfeeding from the other, non-treated breast may be possible if you are not having any drug treatments. 

5. Targeted therapy and breastfeeding

Breastfeeding is not recommended while having or for at least 7 months after the last dose. 

This is because targeted therapy drugs, such as trastuzumab (Herceptin), can be passed to your baby through breast milk.

6. Hormone therapy and breastfeeding

Breastfeeding is not recommended while taking

This is because hormone therapy drugs, such as tamoxifen, may pass through the bloodstream into the breast milk.

7. If you cannot breastfeed

You'll still be able to bond with and care for your baby if you cannot breastfeed. 

Some hospitals may provide donated breast milk for your baby. 

The UK Association for Milk Banking (UKAMB) supports milk banking in the UK. There is strict guidance to ensure donor breastmilk is safe.

Was this helpful?

Was this helpful?
Please tell us what you liked about it.
Please tell us why.
We’re sorry you didn’t find this helpful.
Please do not include personal details and be aware we cannot respond to comments.

Quality assurance

Last reviewed in November 2020. The next planned review begins in November 2023.

  • support-cta-icon-telephone

    Call our free helpline

    If you have any concerns about breast cancer, or just want to talk, our specialist nurses are here for you.

    Lines open: Monday to Friday - 9am to 4pm; Saturday - 9am to 1pm

  • support-cta-icon-email

    Explore ways to talk to our nurses

    It can be difficult to talk to someone in person about breast cancer concerns. Explore other ways you can ask a question.

Share this page