You can breastfeed as normal after most imaging scans, such as CT, MRI and ultrasound scans. There is no need to express and discard breast milk.
Some other examinations, such as nuclear medicine and PET scans, use small amounts of radioactive medicines.
In these cases, you may need to stop breastfeeding for a short time. Your healthcare team will explain any special precautions you need to take.
Breastfeeding after a CT scan
CT or CAT scan stands for computerised axial tomography scan. A CT scan uses x-rays and a computer to create detailed images of the inside of your body. These are used to diagnose and monitor conditions.
You may need a CT scan if you have:
- damage to bones or internal organs
- problems with blood flow
- cancer
You will be exposed to radiation during a CT scan. The radiation does not stay in your body or breast milk after the examination.
It is safe to continue to breastfeed after a CT scan. Your doctor or radiologist may use a contrast material to make the results of the CT scan clearer. The contrast material is a special dye that may be taken as a drink or injected into a blood vessel.
Contrast dyes are usually made of iodine. If the contrast material makes its way into your milk, the amount will be very small. It's safe to continue to breastfeed.
There is no need to remove any of your breast milk with a pump after a CT scan.
Breastfeeding after an MRI scan
An MRI scan takes detailed pictures of the inside of your body. It's used to help diagnose conditions, plan treatment and check how treatment is working.
It is safe to breastfeed after an MRI scan. There is no need to remove any breast milk with a pump after an MRI scan.
MRI scans do not use ionising radiation.
Some MRI scans require a contrast injection to improve the images. Only a very small amount enters breast milk, and this is not harmful to your child.
Breastfeeding after an x-ray
X-rays use a very small amount of radiation to create images of the body. The radiation does not stay in your body or breast milk after the examination.
You can continue breastfeeding immediately after the x-ray. There is no need to express and discard breast milk.
Breastfeeding after ultrasound or Doppler scans
Ultrasound and Doppler scans use sound waves to create pictures of structures and blood flow within the body.
A Doppler scan is often used after childbirth to check blood flow and to check for conditions such as deep vein thrombosis (DVT).
These scans do not use radiation. You can continue breastfeeding immediately after a Doppler or ultrasound scan. There is no need to express and discard breast milk.
Breastfeeding and nuclear medicine scans
Nuclear medicine scans use radioactive medicines that are either injected, swallowed or inhaled. They are used to diagnose and plan treatment for conditions such as cancer.
Diagnostic nuclear medicine scans
After this type of scan, a small amount of radioactivity remains in your body and your breast milk for a short time.
For this reason, you may be told to avoid close contact with babies, young children and pregnant women for several hours after the scan.
How long you should wait varies depending on the type of scan, but is usually up to 24 hours.
Your care team will give you specific instructions for your scan. Contact the team before the scan to tell them you are breastfeeding. This will help you to make arrangements for feeding your baby.
If you need to delay breastfeeding, they may tell you to:
- express breast milk at your usual feeding times - this helps you maintain your milk supply and avoid engorgement
- discard the expressed milk and resume breastfeeding after the interruption period
Nuclear medicine therapy
Nuclear medicine therapies use much larger amounts of radioactivity than diagnostic scans. After the therapy, radioactivity remains in your body and your milk for some time.
Contact your team in advance of your treatment if you are breastfeeding.
You will usually need to stop breastfeeding completely before treatment.
PET scans
A PET scan is a test that uses a small amount of radiation to scan inside your body. It's used to diagnose and plan treatment for conditions such as cancer.
If you have a PET scan, you may be advised to avoid close contact with your baby and other children for a few hours. This is because you may carry a small amount of radiation during this time.
How long to avoid contact and breastfeeding varies, but is usually between 1 and 12 hours after the PET scan.
Your PET team will provide specific instructions for your scan. Contact the team before the scan to tell them you are breastfeeding.
If you need to delay breastfeeding, you may be told to:
- express breast milk at your usual feeding times
- discard the expressed milk and resume breastfeeding after the interruption period
This helps maintain your milk supply while allowing any radioactivity in the breast milk to decay.