The objective of this study was to use an anatomically arrayed whole-body p
hantom to measure radiation exposure to the ovaries and uterus during stand
ard dual-energy Xray absorptiometry (DXA) scanning. DXA instrument manufact
urers' published entrance skin exposure is about 3 mR (0.77 mu C/kg), which
is equivalent to the radiation exposure received during a transcontinental
plane trip. Nonetheless, since DXA scanning is used more frequently with v
ery young females, the need for pregnancy testing has become an issue that
requires attention and formulation of research guidelines. We attached ther
moluminescent dosimeters (TLDs) to anatomically arrayed balloon models for
ovaries and the uterus, and placed these in the appropriate sites within a
small human skeleton along with appropriate amounts of aqueous and fat soft
tissue equivalents. Whole-body scanning with a Hologic QDR-2000W was perfo
rmed 10 times with the pencil beam mode and, using separate TLD detectors,
10 times with the fan beam mode. Overall, the average exposures at skin ent
rance were 0.89 mR (0.23 mu C/kg) with doses for the ovaries of 0.52 mrad (
5.2 mu gy) and 0.59 mrad (5.9 mu gy) for the uterus. These doses are equiva
lent to 2 d of ambient background radiation in central Pennsylvania or 1 h
of flying at 39,000 ft. Although different DXA models by Hologic and DXA in
struments by other manufacturers will have different radiation outputs, we
believe that these low radiation levels do not require pregnancy testing or
questioning of whether the scan subject might be pregnant.