What is the initial treatment of choice for hyperthyroidism in a 10-week pregnant patient?

In the context of a 10-week pregnant patient diagnosed with hyperthyroidism, the initial treatment of choice is propylthiouracil (PTU). PTU is considered the safest option during the first trimester of pregnancy due to its lower risk of teratogenic effects compared to other treatments.

In early pregnancy, controlling hyperthyroidism is crucial since uncontrolled thyroid levels can lead to adverse outcomes for both the mother and the fetus, including complications such as preterm labor and low birth weight. PTU works by inhibiting the synthesis of thyroid hormones, effectively managing the condition while minimizing exposure to the developing fetus.

Other treatment options such as radioiodine treatment are contraindicated during pregnancy due to the potential harm caused by ionizing radiation to the fetus. Subtotal thyroidectomy is generally reserved for cases where medical management fails or when there are significant complications, which is less common as an initial approach during pregnancy. Lastly, not providing any treatment is not advisable, as it leaves the mother and fetus at risk of the complications associated with hyperthyroidism. Thus, PTU is the most appropriate first-line treatment for hyperthyroidism in this scenario.