Radiation Exposure during Pregnancy
During an x-ray exam, the woman is exposed to radiation to produce the x-ray image, and the baby may also be exposed. A small amount of radioactive dye is injected into the woman’s body which may also expose the baby. In most cases, the risk to the baby is very small. The benefit to the woman having the exam (and her baby) outweighs the risks. If you are or may be pregnant we may postpone the exam.
The amount of radiation used is very small. It is about the amount that you are exposed to from natural sources. Effects only happen when the amount of radiation is much higher. The risk to your baby’s health depends on the stage of pregnancy at the time and the amount of exposure.
• The first two weeks of pregnancy after the start of your last period. There is no risk to the baby from radiation.
• During the third week of pregnancy, the baby should be unharmed. There is a tiny chance that radiation could result in a loss of pregnancy.
• During weeks 4-10, the organs of the baby like the heart, lungs, skin, and muscles are starting to develop. At this time, there is a very small chance of causing a birth defect.
• During weeks 10-17, the nerves and the brain are growing. Risks are small for most exams at this stage, though much larger doses or radiation could cause brain damage and mental retardation.
• During weeks 18 until birth, it is unlikely to cause birth defects or other health effects, unless the doses are very large.
• At anytime during pregnancy, there may be a very slight increased risk of cancer later in the baby's life.
What can I do to prevent harm to my child?
Although there are no bad effects for most exams using radiation, we wish to err on the side of safety for you and your child. Before any imaging exam, be sure to let your doctor know that you are pregnant or you think you may be pregnant. You can be certain you are not pregnant if:
• You have not yet started to have periods (and have not had sex) or are postmenopausal.
• You have had a hysterectomy or a tubal ligation, or are reliably using birth control.
• Your sexual partner cannot get you pregnant, even without birth control.
• You have a normal cycle, and your last period began less than 10 days ago.
• You have not had sex since your last period.
When you arrive for your exam, we will talk with you further about this. If you do not feel that you meet the criteria listed above, please come one-hour before your exam for a urine pregnancy test. Go to the Radiology desk. They will order the test for you.
The information provided should not be used during any medical emergency or for the diagnosis or treatment of any medical condition. A licensed physician should be consulted for diagnosis and treatment of any and all medical conditions. Call 911 for all medical emergencies. Any duplication or distribution of the information contained herein is strictly prohibited.
Last Updated: 01/22/2013
Copyright © 01/22/2013 University of Wisconsin Hospitals and Clinics Authority. All rights reserved. Produced by the Department of Nursing. HF#6354
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