Effects of radiation on the fetus and pregnancy

  There are often women around who find out they are pregnant and remember that they had X-rays after menopause or had to undergo X-rays during pregnancy due to various medical emergencies.
  Her relatives and friends, and even some doctors, will tell her that taking X-rays during pregnancy can cause fetal malformation or death, and that the pregnancy should be terminated before it is too late. The mother-to-be must be in a dilemma, so how can we deal with this scientifically? If the mother chooses to keep the baby, she will be scared during the whole pregnancy, after all, everyone wants to have a healthy baby; if the mother abandons the baby, a little life will be killed in the nascent stage. As a reproductive physician, I see such tragedies happen every time and I sigh!
  Indeed, excessive doses of X-rays can cause many serious damages to the fetus, such as miscarriage, fetal growth disorders, malformations, mental development disorders, etc., and can increase the incidence of malignant tumors in children.
  According to clinical guidelines from the American College of Radiology, the American College of Obstetrics and Gynecology, and the U.S. Food and Drug Administration, the vast majority of diagnostic radiological examinations are not harmful to the fetus, and if they are, they are very, very low. A single diagnostic X-ray does not expose the fetus to a dose that would cause embryonic or fetal damage. Therapeutic (e.g., radiation oncology) radiation doses can far exceed the dose of diagnostic radiation.
  According to the American College of Radiology and Obstetrics and Gynecology, the dose to the fetus during a single chest x-ray is 0.02C0.07 mrad, especially between 8 and 25 weeks of gestation. Remember, it takes more than 5000 mrad to cause fetal damage!
  To calculate the dose of radiation exposure for common types of radiology examinations, it is clear that only 70 chest films, 50 abdominal plain films, 5 pyelograms, 7 mammograms, 5 CT examinations of the head and chest, 1 barium enema or small bowel serial imaging, and 1 CT scan of the abdomen or lumbar spine in a short period of time can cause damage to the fetus.
  Usually when X-rays have to be done during pregnancy, the pregnant woman’s abdomen is protected with protective clothing containing lead to further reduce the dose of exposure.
  Therefore, as shown in the table above, except for barium enema, small intestine continuous imaging, abdominal or lumbar spine CT scan, most of the contrast fluorescence examinations will only give millirad dose to the fetus, basically doing 1 or 2 times will not cause significant harm to the fetus. Therefore, if you have a medical condition during pregnancy, or if you have a trauma that requires an x-ray and there is no better alternative, you should not refuse the test for fear of risking the fetus. Your health is of utmost importance not only to yourself but also to your child.
  In our practice, we often encounter mothers who are pregnant and come to the hospital with questions about whether they can have the baby now because they had an X-ray a month before they knew they were pregnant. The situation is such that if the mother-to-be received an x-ray higher than 10 rad within the first two weeks of pregnancy, it may kill the embryo. But it is an all or nothing question, meaning that if the fetus survives, there will be no problem.
  Remember that couples who have not been exposed to X-rays before and during pregnancy and are healthy have a 4% chance of having a malformed newborn, and there is no evidence that pregnant women who have been exposed to X-rays have a higher chance of having a malformed baby than other unexposed mothers-to-be. Deformities in newborns are objective and are not the result of 1 common X-ray examination.
  Ultrasound uses a sound wave, not an ionizing ray.
  To date, there have never been any reports of fetal damage from diagnostic ultrasound, including Doppler ultrasound. Ultrasound is safe during pregnancy, which is why modern obstetrics and gynecology maternity exams do not use x-rays, but routinely use ultrasound. MRI also does not use ionizing rays, but uses a magnetic field to change the energy state of hydrogen ions in the body and image it. Therefore, it does not cause damage to the fetus. Therefore, MRI is the best choice when it is necessary to check the development of the fetal central nervous system or to confirm placenta abnormalities such as placenta praevia.
  American College of Obstetrics and Gynecology guidelines for X-ray examinations during pregnancy.
  1. Pregnant women should be informed that a single X-ray examination is harmless. X-rays of less than 5 rad will not cause fetal damage or cause fetal malformations.
  2. If diagnostic X-rays are needed during pregnancy, concerns about high doses of radiation should not be a reason to prevent or forgo the test. However, if possible, other alternative tests such as ultrasound or MRI can be considered instead of X-rays.
  3. Ultrasound or MRI is safe during pregnancy.
  4.If multiple X-ray exposures are needed, a radiologist should be consulted to calculate the total possible dose of exposure to the fetus in order to guide the diagnosis.
  5.The use of radioactive iodine isotopes during pregnancy is contraindicated and should not be used.
  6. Radioactive contrast agents should be avoided if possible. They should only be considered if the benefits of their use are far greater than the possible damage to the fetus.
  As a pregnant woman, the following is what you should do.
  1. First, and most importantly, tell your doctor if you are pregnant or suspect you are pregnant. It’s not just a matter of taking or not taking X-rays, but for pregnant women, all other medications should be chosen quite carefully.
  2. If you need an x-ray during your pregnancy, remember to tell your doctor if you have had a similar test recently. Maybe this time the test can be omitted.
  3. In short, if you are pregnant, or suspect pregnancy, consult your doctor before doing any tests. There is no need to worry excessively if you have an X-ray without knowing it. A single diagnostic X-ray is not a reason to terminate a pregnancy at will!