I often hear of women who are pregnant after receiving diagnostic radiation, such as chest x-ray, oral x-ray, or abdominal x-ray, or who have to receive x-ray during pregnancy because of illness, and are told by their friends and even by many doctors that the exposure during pregnancy will cause fetal malformations, and that the pregnancy should be terminated before it is too late, and that abortion should be induced. No one wants to have an unhealthy child, so the joy and hope for the baby was immediately replaced by physical and psychological damage. A little life is killed in the embryonic stage.
Does exposure during pregnancy really affect the fetus?
The radiological diagnostic measures that may be received during pregnancy for diagnostic purposes are x-ray exposure, ultrasound, MRI, CT scan, or nuclear medicine diagnosis. Of these, x-ray exposure is the most common and most likely to cause alarm to pregnant women and their families. This stems from the common public perception that x-ray exposure can harm the fetus and even cause malformations. China’s liberal abortion policy has in turn led to the very common choice of abortion by pregnant women to avoid the possibility of malformation.
It is true that high doses of ionizing radiation such as x-rays can cause many serious damages to the fetus, such as miscarriage, fetal growth disorders, microcephaly, impaired mental development, and increased risk of childhood malignancies.
But are diagnostic x-rays dangerous?
According to the clinical guidelines of 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 do not cause fetal harm, and if they do, it is very, very low. The American College of Radiology clearly states that the dose of exposure from a single diagnostic x-ray does not reach a dose that would cause embryonic or fetal harm. Therefore, a single diagnostic x-ray does not justify an abortion. I emphasize the word diagnostic again and again here, because the dose of therapeutic radiation can far exceed that of diagnostic radiation, which is a different matter.
Some women have been exposed to radiation for some reason before they knew they were pregnant, and the fear and misguided advice of some doctors has led these women to bite the bullet and choose abortion for the sake of a healthy child. Once a child is conceived, it is still possible that some disease or accident may require the use of x-rays to make a correct diagnosis. Let’s look at the data to see if diagnostic tests can cause fetal damage or even malformations.
If the fetus receives less than 50 mGy (gy is a unit of radiation dose, 1 gy is equal to 100 rad, 50 mGy is 5 rad, which is equal to 5000 mrad), it will not cause any health effects to the fetus. Fetal health problems can only occur if the fetus is exposed to doses higher than 100 mGy, especially 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 only 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 irradiate the fetus up to 3.5 rad.
In other words, a plain x-ray usually exposes the fetus to a very small dose of radiation. In addition, when x-rays are needed during pregnancy, the abdomen is usually protected with a protective garment containing lead, which further reduces the 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 you do need an x-ray during pregnancy due to illness or trauma and there is no better alternative, there is no need to refuse the test for fear of risk to the fetus. Your health is of utmost importance not only to yourself but also to your child.
Can exposure before I know I’m pregnant affect 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 problem, meaning that if the fetus survives, there will be 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.
So is ultrasound harmful to the fetus?
Ultrasound uses a sound wave, not an ionizing ray. So far, no reports of fetal damage from diagnostic ultrasound have ever appeared, including Doppler ultrasound. Ultrasound is safe during pregnancy, which is why modern obstetrics and gynecology exams do not use x-rays, but routinely use ultrasound.
So is MRI safe?
MRI also does not use ionizing rays, but uses a magnetic field to change the energy state of hydrogen ions in the body and imaging. Therefore, it will 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 diagnose placenta abnormalities such as placenta praevia.
Therefore, the specific guidelines given by the American College of Obstetrics and Gynecology regarding x-ray examinations during pregnancy are
1. Pregnant women should be informed that a single x-ray is not harmful. An x-ray exposure of less than 5 rad will not cause fetal damage or cause malformations.
2. If diagnostic x-ray exposure is needed for diagnostic testing during pregnancy, concerns about high doses of radiation should not be a reason to prevent or forgo testing. However, if possible, other alternative examinations, such as ultrasound or MRI, can be considered instead of x-ray examination.
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. Use should be considered only if it is ensured that the benefits of use far outweigh the possible damage to the fetus.
For pregnant women the following are precautions.
1. First, and most importantly, tell your doctor if you are pregnant, or suspect pregnancy. This will be important not only for x-ray exposure, but also for other medication choices.
2. If you need x-rays during your pregnancy, remember to tell your doctor if you have had similar tests recently. Maybe this time the test can be omitted.
3, In short, if you are pregnant, or suspect pregnancy, consult your doctor, no matter what aspect of the test is being done. But it is unnecessary to do unnecessary worrying, not to mention the reason for abortion.