X-rays during pregnancy

It’s best to avoid X-rays during pregnancy. Of course, sometimes they can’t be avoided, and some pregnant women have Xrays before they know they’re expecting. So, how risky are they?

Do pregnant women need to be careful around X-rays?

Xrays used for medical exams have enough energy to damage cells and DNA. In addition, fetuses are particularly sensitive to X-rays because their cells are rapidly dividing and their organs are still developing.

That being said, the risks of Xrays should not be overstated, as this can cause unnecessary stress for pregnant women who need to have one.

What are the risks of getting an X-ray during pregnancy?

In general, X-rays used for diagnostic purposes do not expose you to radiation levels that could harm your baby.

The risk of birth defects, certain illnesses such as leukemia, and miscarriages appears at very high doses of radiation, that is, above 100 mSv. However, the radiation doses patients are exposed to during an X-ray range from 0.01 mSv (dental Xray) to 8 mSv (abdominal CT scan where the area being examined is scanned by several X-rays).

Xrays taken of areas outside the abdominal area, such as the upper body (head, teeth, arms, chest) or the legs, are not considered to pose a risk to the baby. This is because the Xray beam is focused on the area being examined, protecting the fetus from all but a negligeable amount of radiation.

When Xrays are taken of the pelvis, abdomen, lower back, or kidney area, the Xray beam may reach the fetus. However, modern equipment and techniques mean a lower dose of radiation can be used.

Therefore, experts agree that properly performed X-rays do not significantly increase the risk of birth defects, disease, or miscarriage.

If multiple abdominal CT scans are needed, the radiation dose could be higher due to the repeated exposure to Xrays in a single sitting. A dose and risk assessment should be performed in these cases.

How can you minimize the risks?

Tell your doctor or dentist if you are pregnant or think you might be pregnant. They will assess whether the benefits of an X-ray outweigh the risks. If possible, they may choose to postpone the Xray or use another test instead.

Your doctor may still need to do an Xray to get the information they need to treat you appropriately. You should tell the radiographer that you are pregnant at the time of your examination. That way, they can take any additional precautions and choose the most suitable technique.

If you had any Xrays before you knew you were pregnant, tell your health care provider at your first pregnancy follow-up appointment.

Things to keep in mind

• It’s best to avoid X-rays during pregnancy.
• However, the risk associated with Xrays is low because the dose of radiation you are exposed to is small, and when the radiation does not reach the fetus, the risk is even lower.
• Tell your doctor or dentist if you are pregnant or think you might be pregnant.

Scientific review: Mario Chrétien, Eng. M.Sc., medical physicist and head of radiation protection, CHU de Québec - Université Laval Research and copywriting:The Naître et grandir team Updated: February 2022

Photo: GettyImages/milanvirijevic