Q. A 32-year-old G2P1 woman comes to her obstetrician at 8 weeks of pregnancy for a routine antenatal visit. Her medical history shows that she is a known case of Graves disease and is on methimazole for the past 6 months. She says that it is an unplanned pregnancy. She is also worried that her thyroid disorder and the medication may harm her pregnancy. Her temperature is 98.4°F (36.9°C), pulse is 106/min, blood pressure is 120/90 mmHg, and respirations are 14/min. Physical examination shows a mild diffuse enlargement of the thyroid gland with no lymphadenopathy. The serum beta hCG test is positive for pregnancy. Laboratory investigations are shown below. Which of the following is the most appropriate next step in her management?