Breastfeeding and contrast enhanced CT and MRI scan

Introduction

Until recently, many individuals referred for contrast scans were advised to abstain from (stop) breastfeeding for 24-48 hours after a scan.

This advice was not based on evidence of harm to the infant and did not consider the difficulties of expressing milk for 24 hours, bottle feeding, and the risk of mastitis for the mother.

This page provides information about new guidance for breastfeeding people undergoing contrast-enhanced MRI and CT scans.

MRI scans, MR contrast, and breastfeeding

What is an MRI scan?

A magnetic resonance (MR) scanner uses a very strong magnetic field and radio waves to produce images of the body. This does not use ionizing radiation like X-rays and there are no known long-term health risks.

What is MR contrast?

MR contrast is a liquid dye that is used to enhance the appearance of anatomy during an MRI scan. It contains gadolinium, which sometimes may remain in the body after a scan where contrast is administered. There is no evidence that this has caused any harm to patients.

Can I breastfeed after receiving MR contrast?

There is limited research into gadolinium contrast and breastfeeding, however several studies have shown that:

0.04% of the administered dose of contrast medium is excreted into breast milk.
Less than 1% of the contrast medium in breast milk, ingested by an infant, is absorbed from the gastrointestinal tract.

Therefore, the expected dose of contrast medium absorbed by an infant from ingested breast milk is extremely low at 0.0004%.

Recent guidance issued by the Royal College of Radiologists and Society of Radiographers says that no special precaution or stopping breastfeeding is recommended before an MRI scan with contrast.

If, however, you do remain concerned about breastfeeding after a contrast scan, some individuals wish to abstain from breast-feeding for 24 hours following the scan. If you choose this option, you may wish to consider pumping and disposing of breastmilk to reduce the risk of developing mastitis.

There is no reason to abstain for more than 24 hours.

CT scans, CT contrast, and breastfeeding

What is a CT scan?

Computer tomography (CT) scanning uses X-rays to produce images of organs or vessels in the body. There are no known long term side effects from having a CT scan, however any radiation to the body slightly increases a person’s chance of developing a cancer later in life.

What is CT contrast?

Contrast medium is given to enhance the appearance of different structures during the scan. An iodine-based contrast is used, and this may pass in small amounts to the breastmilk.

Can I breastfeed after receiving CT contrast?

Studies have shown <1% of iodine-based contrast may pass into the breastmilk, however no negative effects have been reported with contrast in breastfeeding infants:

Only 0.5% of the radiocontrast dose used in the mother would be ingested by the infant.
<0.1% of contrast ingested by an infant would be absorbed from their gut into their bloodstream.

Recent guidance issued by the Royal College of Radiologists and Society of Radiographers states that no special precaution or stopping breastfeeding is recommended before a CT scan with contrast.

Where can I breastfeed in the hospital?

You are welcome to breastfeed anywhere on site, however if you would prefer to have a private room, dedicated breastfeeding rooms are located:

Near every lift well in the Atrium. Rooms are next to the giant letters (A, B and C) round the right-hand side of the lift doors.
A further room is located near the Brunel car park entrance.

What will happen if I choose not to have contrast?

The decision to have contrast is entirely yours. It will not affect any aspect of your care within the imaging department. It may mean that your diagnosis is not quite as specific, which may potentially impact your treatment plan. Please discuss this with your referring clinician.

What if I am or think I might be pregnant?

MRI

MRI Please contact us if you think you may be pregnant – it is not advised to have gadolinium based contrast media whilst pregnant

CT

Use of iodinated contrast is generally safe during pregnancy, This will be carefully considered prior to administration.

How can I prepare for a contrast enhanced scan?

The day before your scan, slightly increase your fluid intake (drink more) and continue to do this for the following 24 hours to ensure you are well hydrated.

On the day of your appointment, please refer to any specific dietary instructions which, if required, will be stated on your appointment letter.

Please contact the department prior to your scan if you have

Reduced kidney function or diagnosed kidney failure.
You are on or have ever been on dialysis.

What options are available to me?

You can decide to receive contrast and continue breastfeeding as normal.
Prior to your appointment - express sufficient breastmilk (and store appropriately) to bottle/cup feed the child for 12 – 24 hours. After the scan, express and dispose of breastmilk for the following 12- 24 hours.
You can decide to have a plain (non-contrast) scan with review to see if contrast is necessary for diagnosis. Your doctor or clinical nurse specialist will have considered the potential risks and benefits of having a scan involving contrast when referring you. (For accurate diagnosis it is not always possible to have a non-contrast scan).

What happens during a contrast scan?

Contrast is normally injected via a cannula or line which is placed in a vein, usually in your arm. The cannula will stay in your vein until your procedure has finished. You will be monitored and observed throughout and advised when the contrast is about to be injected. This could be a manual injection by a member of the team or by an injector pump.

In MRI, you may feel a cool sensation in your arm when the injection starts. These side effects are temporary.

In CT, you may feel a warm sensation passing around your body and a metallic taste in your mouth. These side effects are temporary.

What happens after my contrast scan?

We will ask you to remain in the department for a short period of time, to observe you and remove the cannula. We will leave the cannula in place incase we need to give you any other medication. We will check to make sure you feel well enough to leave and remove the cannula.

Please do not leave the department with your cannula still in place unless you have another procedure requiring its use within the hospital.