In pregnancy, which imaging modality is avoided due to radiation exposure when evaluating a breast lesion?

• A. CT
• B. Mammography
• C. Ultrasound
• D. Breast MRI

Answer: (B)

The main idea is to minimize fetal exposure to ionizing radiation when imaging during pregnancy. Ultrasound is the go-to because it uses sound waves, with no radiation, and is safe for evaluating a breast lesion. MRI also does not involve ionizing radiation, so it can be used when ultrasound isn’t conclusive, though gadolinium contrast is avoided during pregnancy. CT and mammography both rely on X-ray radiation; while CT isn’t typically used for breast lesions in pregnancy, mammography directly involves radiation to the breast. Even with shielding, the fetal radiation exposure is a concern, so mammography is generally avoided during pregnancy unless there is a compelling, urgent indication.