If a patient requires multiple scans and repeated doses of radiation, a consultation with a qualified medical physicist should be considered to determine estimated fetal dose
," says Dr.
Studies through the gravid uterus, such as radiographs of the abdomen and lumbar spine, result in a fetal dose of 1 mGy to 3.
The fetal dose for a CT head is 0 mGy and for a CT chest is 0.
Since the fetal dose from a CT scan through the abdomen and pelvis is < 50 mGy, teratogenic effects are not a concern to the fetus when exposed to a single exam.
A low-dose CT KUB results in a reduced fetal dose compared to a routine CT abdomen and pelvis with contrast in the order of approximately 10 mGy to 11 mGy.
In the seriously injured patient, the mother may require several studies with ionizing radiation through the gravid uterus, and the fetal dose may exceed 50 mGy.
Despite the estimated 10-fold lower fetal dose, mean levels of BaP-DNA adducts as determined by high-performance liquid chromatography-fluorescence were comparable in paired New York City newborn and maternal samples (0.
There are no data in humans on maternal versus fetal dose of PAHs.
These preliminary results indicate a need for further research, especially as the fetal dose
from maternal exposure is unknown.
However, official estimates of fetal doses
after the Chernobyl explosion, even in the most contaminated regions of Germany, were < 1 mSv (UNSCEAR 2000), far below the presumed safe threshold.
A highly statistically significant excess relative risk (ERR) associated with a diagnostic X-ray examination of 40% was obtained from the Oxford Survey, but reliable estimates of fetal doses
appropriate for this study are not easily derived (Mole 1990).