An example of a radiographic study using natural shielding to decrease radiation to the ovaries is:

• A. AP T/S
• B. AP Pelvis
• C. Lateral Femur
• D. PA Lumbar Spine

Answer: (B)

Gonadal protection can come from the body's own anatomy when the beam is focused in a region where dense structures between the beam and the gonads attenuate much of the radiation. An AP pelvis study uses the pelvic bones as a natural shield: the ovaries lie within the pelvic ring and the thick bones between the beam and those organs absorb a portion of the exposure, reducing the dose to the ovaries without needing external shielding. Other projections either do not image the pelvis (so gonadal dose isn’t a concern in the same way) or place the gonads more directly in the beam path, so they don’t illustrate this natural shielding as effectively.