Thyroid Disorders USMLE Step 1 Practice Question
A 28-year-old woman at 8 weeks gestation presents for prenatal screening. Her TSH is 0.2 mIU/L (normal pregnancy range: 0.1–2.5) and free T4 is normal. She has no symptoms of thyroid dysfunction. She has a history of Graves disease treated with radioactive iodine 2 years ago. Which of the following is the most appropriate management?
Answer choices
- ANo thyroid medication needed; recheck TSH each trimesterCorrect answer
- BMeasure thyroid-stimulating immunoglobulin (TSI) levels
- CStart levothyroxine to normalize TSH to >1.0 mIU/L
- DStart propranolol to prevent fetal tachycardia
- ERepeat radioactive iodine treatment to prevent relapse
- FStart antithyroid medication (propylthiouracil) to suppress TSH and prevent thyroid storm
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