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Risks of Radiation in Medical Imaging
Radiation risk during pregnancy
Pregnant women should be aware that radiation from imaging tests has risks for the fetus. If women need to have an imaging test, they should tell their doctor whether they are or may be pregnant. Doctors also consider whether the woman may be pregnant and not know it. However, x-rays, if necessary, can be done in pregnant women. During diagnostic tests, the examiner protects the fetus from exposure to radiation by covering the woman’s abdomen with a lead apron. The risk to the fetus depends on When during the pregnancy a test is done Which part of the mother’s body is x-rayed During pregnancy, the time when risk is greatest is when organs are being formed, during the 5th to 10th weeks of pregnancy. At this time, radiation can cause Overview of Birth Defects . Earlier during pregnancy, the most likely problem to develop is a X-rays of parts of the mother's body that are far away from the fetus, such as the wrists and ankles, expose the fetus to less radiation than x-rays of closer parts, such as the lower back. Also, x-rays of smaller body parts, such as fingers and toes, require less x-ray energy than x-rays of larger body parts, such as the back and pelvis. Because of these facts, x-rays that do not involve the abdomen have little risk, regardless of when they are done, particularly if a lead shield is worn over the uterus. Thus, if x-rays are necessary (for example, to evaluate a broken bone), the potential benefit usually outweighs the potential harm. 