Mercury Safe Dentists: Articles

Dental X-rays and Low Birth Weight Babies

Low Birth-Weight Babies and Dental X-Rays

Pregnant women who undergo dental X-rays may raise their risk of having low birth-weight babies, researchers said on Tuesday. 

The association could be related to exposing the mothers' thyroid, pituitary or hypothalamus glands to radiation, even early in the pregnancy. 

"Up until now, people assumed that head and neck radiation will not have any adverse effects on pregnant women. They assumed that only direct radiation to the uterus or the fetus would be associated with adverse pregnancy outcomes," said Philippe Hujoel of the University of Washington in Seattle, who led the study. 

But a seven-year review of a dental insurance company's records in the state of Washington found pregnant women who underwent extensive dental X-rays were at three times the risk of having a low birth-weight baby, characterized as weighing 5.5 pounds (2.5 kg) or less. 

Some 20 percent of the 5,585 infants in the study had low birth weight. 

The study, published in the Journal of the American Medical Association, divided women into three groups, with the highest level of radiation exposure from dental X-rays comparable to that received in four to 16 round-trip flights between New York and London. 

"Since women may not always be aware of their pregnancy status, it may not be possible to eliminate all dental radiography during pregnancy, but if this goal could be achieved and if the identified association is causal, the prevalence of (term low birth-weight) infants could be reduced by up to 5 percent," the report said. 

CHICAGO (Reuters) -Tue 27 April, 2004 21:10

Tom McGuire, DDS: Comment

This is an important study and should be taken seriously by every woman who is now pregnant or is planning a pregnancy. In the study, not every pregnant woman who was exposed to dental X-rays delivered a low birth-weight baby but the risk was still one-in-five and there is no way to predict in advance if you will, or won’t, be in the high-risk group. I can’t speak for you but even if it were 1%, I wouldn’t take the chance if only for my baby’s sake. Particularly when there are things you can do to protect yourself and the fetus. Now that you are aware of the problem I’ll offer the following recommendations:

  • Inform your dentist that you are, or may be pregnant and are concerned about dental X-rays.
  • If you even think it is a possibility that you are pregnant don’t have a dental X-ray taken unless it is an emergency situation.
  • If you have to have an X-ray taken the least harmful type is a digital X-ray. I’d check with your dentist’s receptionist to see if he or she uses digital X-rays and if not, I’d consider changing dentists. (More and more dental offices are using digital X-rays and they are believed to reduce your exposure to X-rays by up to 90 %.).
  • Make sure you are not only provided with the lead chest protector, but one that covers neck. If it isn’t provided, ask for it and don’t have an X-ray taken without it.
  • Make sure you have a full dental examination, including X-rays if needed, prior to becoming pregnant.

If the examination determines you have an emergency situation, or a potential one, have it dealt with prior your pregnancy. 

Please keep in mind that dental X-rays aren’t the only oral health issue that can affect the health of you and the fetus. Gum disease is a concern and so are mercury-amalgam fillings. I strongly recommend that you deal with these oral health problems before you become pregnant. In this case, because you are responsible for another being, an ounce of prevention is worth much more than a pound of cure. Important information regarding the effects of chronic mercury poisoning from amalgam fillings can be found by Clicking on Chronic Mercury Poisoning.

In Health,


Dr. Tom