Fetal x-ray exposure at doses below 50 mGy (gy is a unit of radiation dose, 1 gy equals 100 rad, 50 mGy is 5 rad, which is equal to 5000 mrad) is not likely to cause fetal health effects. Fetal health problems can only occur at doses above 100 mGy, and are most sensitive between 8 and 25 weeks of gestation. 100 mGy is not used at all for normal diagnostic x-rays, except for barium enemas, small bowel serial imaging, or radiotherapy, where such high doses are possible. According to the American College of Radiology and Obstetrics and Gynecology, the dose to the fetus in the abdomen from a single chest x-ray is 0.02C0.07 mrad. Remember, fetal damage can occur at doses higher than 5000 mrad. A single abdominal radiograph can expose the fetus to 100 mrad, a pyelogram can expose the fetus to more than 1 rad, a mammogram can expose the fetus to 7-20 mrad, a barium enema or small bowel serial imaging can expose the fetus to 2-4 rad, a cephalothoracic CT can expose the fetus to less than 1 rad, and a CT scan of the abdomen or lumbar spine can expose the fetus to less than 1 rad. CT scan of the lumbar spine can expose the fetus up to 3.5 rad. To explain in simple terms. Plain x-rays usually expose the fetus to only a very small dose of radiation. And usually when x-rays are needed during pregnancy, the abdomen is protected with a protective garment containing lead, which further reduces the exposure dose. Most contrast fluoroscopies, with the exception of barium enemas and small bowel serial imaging, will only give a millirad dose to the fetus, and the number of exposures and distance to the slice will vary with CT. CT of the pelvis may expose the fetus to as much as 1.5 rad, but radiologists can reduce this to nearly 250 mrad by using low-dose techniques. In late 2013, the American College of Obstetricians and Gynecologists published new guidelines on dental care during pregnancy and for the first time unambiguously said that early oral health care, oral cleanings, including dental x-rays, are recommended during pregnancy. So, it can be summarized. Routine dental x-rays, head x-rays, extremity x-rays, and chest x-rays, including mammograms, or head and chest CT are not harmful to the fetus, and the increased risk of cancer in childhood is negligible. Please discuss with your doctor if you need an abdominal exam. Therefore, if an x-ray is needed during pregnancy due to a medical condition or trauma and there is no better alternative, there is no need to refuse the test for fear of risk to the fetus. If a woman is exposed to x-rays above 10 rads within the first two weeks of pregnancy, it may kill the embryo. But this is a 0 or 1 issue, meaning that if the fetus survives, there is no problem. But what happens when a pregnant woman gets a chest x-ray and her baby is deformed? Remember, without exposure, the same 4-6% of newborns will have various types of malformations, but the vast majority will be minor, such as a birthmark, an extra finger or toe, etc. A child with malformations is not the result of diagnostic radiation.