Dental X-rays and Pregnancy: Radiation Safe for Baby
Probably one of the most discussed dental and pregnancy topics is the safety of having dental X-rays taken while being pregnant. The fear is that exposure of the fetus to the radiation needed to take the dental X-rays will result in birth defects or low birth weight.
As a general rule of practice, dentists and physicians and radiologists will avoid prescribing an X-ray if they know you are pregnant, so it is very important that you report to them, even if you just think you might be pregnant when they ask. Some women are very offended when asked such a personal question, but it really is very important.
Radiation Affects Growing Cells
It is pretty much accepted that radiation can “disrupt normal processes of the cells, causing them to grow abnormally or to die.” (Duke) Embryos (within the first trimester) are most susceptible to possible radiation effects because “the cells of the developing baby are rapidly dividing and growing into specialized organs and tissue.” (ASRT)
In 2004, a group of scientists at the University of Washington released the results of their study of over 1,100 low-birth-weight births that showed a possible connection between exposure to X-ray radiation (specifically four bitewing dental X-rays) and an apparent doubled increase in risk of having a baby weighing less than 5.5 pounds. About 10 percent of those cases reported having had dental X-rays performed while they were pregnant.
There are several conclusions that can be derived from this study. First, the scientists concede that many of these instances probably happened without the patient or the dentist knowing that the patient was pregnant at the time of the X-rays.
Second, there was no investigation as to the mother’s oral hygiene status while pregnant in the light of several research projects that show a strong link between periodontal disease and low-birth-weight babies (low birth weights are seven times more likely with periodontal disease). Iit is entirely possible that this condition, and not necessarily the X-rays on their own, resulted in low birth weights. And it may have been for this reason that the bitewings were taken as these types of X-rays are used to diagnose and track extent of cavities.
Third, the study was conducted between 1993 and 2000 when lead aprons were used to protect the fetus from direct X-ray beams, and an additional lead collar was not used to protect the thyroid and pituitary glands. During dental X-rays, the beams are only directed at the teeth, there is an extremely minute chance even without the lead apron that unborn babies will actually be exposed to direct X-ray radiation.
However, thyroid and pituitary glands are closer to the dental X-ray site. Most lead X-ray aprons now have this collar to protect the thyroid and pituitary glands. Since these glands play an integral role in fetal development and pregnancy hormone levels, it is entirely possible that exposure of these glands to X-ray radiation could have resulted in or contributed to these low birth weights.
Obviously, this issue requires more research, and many doctors and dentists warn against panicking over these results.
Safe and Unsafe Levels of Radiation
There are two types of measurements used to measure radiation exposure and effect on the human body: rems and rads. Rems measure the biological effect of different types of radiation on the human body – basically the unit of biohazardous material. A rem is actually very large, so radiation exposure is usually recorded in millirems (or thousandths of a rem). Rads measure the amount of radioactive energy absorbed by the body, but not the effects of the radiation on the body itself, again, usually expressed in millirads (1000 millirads = 1 rad). (Jefferson Lab)
“On average, Americans receive a radiation dose of about .62 rem (620 millirem each year) [and] about half of this comes from natural background radiation … [and] [t]he other half … from man-made sources … [and] has not been shown to cause humans any harm.” (NRC) Approximately 96% of all exposure to man-made radiation can be attributed to X-rays. Studies have shown that the risks of mental retardation and eye abnormalities in an unborn baby increase at exposure to over 10 rads (10,000 millirads). Dental X-rays expose your baby to .01 millirads or radiation, meaning it would take 100,000 dental X-rays to reach exposure to 1 rad, and 1,000,000 dental X-rays to reach 10 rads.”
Part of the environmental exposure to radiation we experience every day comes from the food we eat, the ground we walk on, the house we live in and the air we breathe. “[T]he average person receives an average internal dose of about 30 millirem of these materials [potassium-40, radium-226, dissolved uranium and thorium] per year from the food and water that we eat and drink.” (NRC) More information about our daily exposure to radiation can be found in the links included below.
As a standard practice, dentists and doctors will put off taking elective X-rays to avoid any possible chance of direct exposure of an unborn baby to radiation, even though, as we’ve seen above, the possibility of such a thing happening to a level where it could harm cell development is extremely unlikely.
However, there are occasions where a woman may not know or even suspect she is pregnant at the time of the X-ray, or, for necessary dental reasons may require an X-ray while pregnant. Make sure that the lead apron you wear for the X-ray includes a collar. If it does not, ask for one. If they do not have one, you have the right to say no to the X-ray.
Remember, though, that dental X-rays make it possible for dentists to see and treat the dental problem you have, there is increased risk to you if they proceed with treatment without looking at X-rays to help show them what the problem is and what needs to be done to treat it. Indeed, many dentists will not proceed with any form of treatment without an X-ray. However, any untreated tooth or dental issue can lead to bigger issues down the road (either long-term or short-term depending on the extent of the problem at the time).
There is no reason to panic over dental X-rays while being pregnant. As shown above, radiation exposure to dental X-rays is extremely minimal compared to other natural sources, but it is important to be informed. If you are concerned, discuss it with your dentist and family doctor before proceeding with treatment.
Darlene Oakley is a freelance writer for EmpowHER.com.
Doses in Our Daily Lives. United States Nuclear Regulatory Commission. Web. Mar 5, 2012.
Natural Background Sources. United States Nuclear Regulatory Commission. Web. Mar 5, 2012.
Everyday Exposure to Radiation. Department of Chemistry, Duke University. Web. Mar 5, 2012.
Can dental X-rays harm my baby? AmazingPregnancy.com. Web. Mar 5, 2012.
Dental X-rays Tied to Low Birth Weight. WebMD. Web. Mar 5, 2012.
Pregnancy and X-Rays: Good or Bad? American Pregnancy Association. Web. Mar 5, 2012.
Pregnancy and X-ray Safety. American Society of Radiologic Technologists. Web. Mar 5, 2012.
Units of Measurement. Jefferson Lab. Web. Mar 5, 2012.