X-rays are a type of penetrating radiation that, depending on the dose, can reduce cell
division, damage genetic material, and harm unborn children. Cells that divide quickly are
very sensitive to x-ray exposure. Unborn children are particularly sensitive to x-rays
because their cells are rapidly dividing and developing into different types of tissue.
Exposure of pregnant women to sufficient doses of x-rays could possibly result in birth
defects or illnesses such as leukemia later in life. With most x-ray procedures,
relatively low levels of radiation are produced. However, a doctor may decide to postpone
or modify abdominal or lower back x-rays in a pregnant woman unless absolutely necessary.
Women who receive x-rays before realizing they are pregnant should speak to their doctors.
Some pregnant women may be exposed to x-rays in the workplace; therefore, the federal
government has established limits to protect unborn children from radiation exposure in
X-rays are a type of penetrating radiation (NRC Glossary, 2000).
Exposure to x-rays is measured in units of radiation absorbed dose (rad), the amount of
radiation absorbed per unit mass of material. Rads are often converted to units of rem by
multiplication with quality factors to account for biological damage produced by different
forms of radiation. The quality factor for x-rays is 1, so rads and rems are equivalent (NRC 10
Depending on the dose, exposure to x-rays can result in diminished cell division,
damage to genetic material, and damage to unborn children (USNRC 2009) FDA CDRH
2001). Rapidly developing cells are very sensitive to x-ray exposure (FDA CDRH 2001). It is important
to note that x-rays affect only those body tissues which come into direct contact with the
beam. The FDA (FDA CDRH 2001)
notes that, "During most x-ray examinations like those of the arms, legs,
head, teeth, or chest your reproductive organs are not exposed to the direct x-ray
beam. So these kinds of procedures, when properly done, do not involve any risk to the
unborn child. However, x-rays of the mothers lower torso abdomen, stomach,
pelvis, lower back, or kidneys may expose the unborn child to the direct x-ray
beam. They are of more concern."
Depending on the dose, x-rays could potentially harm an unborn child. The FDA (FDA CDRH 2001) stated that,
"There is scientific disagreement about whether the small amounts of radiation used
in diagnostic radiology can actually harm the unborn child, but it is known that the
unborn child is very sensitive to the effects of things like radiation, certain drugs,
excess alcohol, and infection. This is true, in part, because the cells are rapidly
dividing and growing into specialized cells and tissues. If radiation or other agents were
to cause changes in these cells, there could be a slightly increased chance of birth
defects or certain illnesses, such as leukemia, later in life."
Women who have been x-rayed before realizing they are pregnant should discuss this with
their doctors. All women who are or may be pregnant should inform their doctors before
being x-rayed. Informing doctors about a possible pregnancy allows them to weigh the risks
and benefits. The FDA (FDA CDRH
2001) states that, "
the doctor may decide that it would be best to cancel
the x-ray examination, to postpone it, or to modify it to reduce the amount of radiation.
Or, depending on your medical needs, and realizing that the risk is very small, the doctor
may feel that it is best to proceed with the x-ray as planned. In any case, you should
feel free to discuss the decision with your doctor."
Federal laws have been established to protect the unborn children of women exposed to
radiation in the workplace. In the workplace, the dose of radiation to an unborn child
throughout the entire pregnancy cannot exceed 0.5 rem. For x-rays, rem and rad are
equivalent and the limit of exposure for unborn children is therefore 0.5 rads (NRC 10