PATH 1: Early Stage Breast Cancer

PATH 2: Neoadjuvant Therapy

PATH 3: Pregnancy During Breast Cancer


PATH 5: Metastatic Stage 4

Pregnancy During Breast Cancer

Being diagnosed with breast cancer during or shortly after pregnancy can be especially worrying, but there are many women who have gone on to have a successful pregnancy while undergoing treatment. 
Pregnancy-associated breast cancer refers to breast cancer dignosed during pregnancy or up to one year after giving birth. 


Treatment of pregnancy-associated breast cancer involves the same components as any other breast cancer, but sometimes there are modifications in the timing of treatments and the performance of certain tests. Your medical team will also be slightly different, as your obstetrician will be included. 
The timing of your diagnosis within your pregnancy may affect the timing of certain treatments. 

Considerations by trimester

First trimester (zero to 13 weeks): If your breast cancer is early stage and the likelihood of receiving chemotherapy is low, a mastectomy with axillary lymph node surgery is a good option as the need for radiation may be eliminated. 

If your breast cancer is a higher stage and/or chemotherapy will be recommended, you can begin with surgery (either mastectomy or breast conserving surgery (BCS) with axillary lymph node surgery), then you can proceed with chemotherapy starting in 2nd trimester, and radiation can be started after delivery of the baby. 

Second trimester (14 to 27 weeks) or third trimester (28 to 40 weeks):  Either mastectomy or BCS surgery with axillary lymph node assessment are both options for your surgical treatment. Your surgery can be followed by chemotherapy during your pregnancy, and then if you require radiation, this can be administered after your delivery. If you are later in your pregnancy, chemotherapy or radiation can begin after delivery. In some cases, patients are induced at or around 35 weeks in order to proceed with adequate treatments for breast cancer. 

If your breast cancer is a higher stage and/or chemotherapy will be recommended, you can begin with chemotherapy during your pregnancy and have surgery later in your pregnancy or after delivery. 


If you need staging, the imaging can be modified during pregnancy to avoid tests with excess radiation to the fetus. Chest x-rays can be safely administered with shielding of the fetus, similar to mammography. An abdominal ultrasound can be used to assess organs within the abdominal cavity (e.g. liver). To assess for bone metastases, an x-ray of a specific area of concern or an MRI may be considered as an alternative to a total bone scan. 

Maintaining your pregnancy

When pregnancy-associated breast cancer patients are compared to non-pregnancy breast cancer patients with the same stage of tumour, the outcomes are similar. Therefore, maintaining your pregnancy during your breast cancer treatments will not affect your overall outcome.

A decision to proceed with termination of the pregnancy should take into consideration with your prognosis, future fertility options and your treatment plan. Of course, these decisions are difficult, personal and individual. 

This guideline from Royal College of Obstetricians and Gynaecologists may be helpful to you.


You should discuss breastfeeding options with your medical team; however, it is not advised for women to breastfeed while on chemotherapy or taking tamoxifen. 


Ensure the exact dates of your pregnancy and precise gestational age to help guide management of your breast cancer. Ensure you are seen by a multidisciplinary team, including an obstetrician, breast surgeon, medical oncologist and radiation oncologist. 

At this point, you may be preparing to tell your loved ones about your diagnosis if you haven't already. This is a personal decision, but confiding in someone may provide you with some emotional support. 

You may also decide that participating in clinical trials is the right choice for you. Again, this is a personal decision, but many options are available.  


It's very upsetting to be diagnosed with breast cancer while pregnant, whether you're a new mother or have already started a family. Remember that you are not alone, and there are many community networks for you to openly talk about what you're going through. You may find that reading other women's stories is beneficial. 

You may have a variety of feelings—from being scared to angry, sad, bewildered, and out of control. These feelings are common, normal and expected. Your personal and medical support team can help you work through them. Our resource directory may also help guide you through your feelings. 


You will be meeting with your breast surgeon, obstetrician, medical oncologist, radiation oncologist and family physician. 

Ideally, you should prepare for your appointment and bring along someone who knows you well and can be a second set of ears during the consultation. You might consider recording your appointments on your smart phone as well.