During pregnancy, which factors necessitate adjusting levothyroxine dose in hypothyroid women?

• A. hCG stimulates TSH receptors early; increased thyroid-binding globulin; dose typically increases ~25-30% after pregnancy confirmation; trimester-specific TSH targets
• B. Decreased estrogen leads to lower TBG; dose decreases
• C. No change in dose required
• D. Dose must be doubled immediately in first trimester

Answer: (A)