A 45-year-old farmer reports experiencing episodes of sweating and feeling hot for the past 6 months despite the cold weather. She denies fever, cough, or pain but mentions mild wheezing during extreme cold. She notices that her face, neck, and chest flush, particularly after eating, prompting her to wear lighter clothing. Over this period, she has gained 7 pounds with no changes in appetite and has observed slight irregularities in her menstrual cycle, including spotting a week before her periods. Her last Pap smear was done last year and was normal. She has been sexually active in a monogamous relationship with her husband for the past 10 years. On physical examination, a temperature of 36.25 °C (98.5 °F), a pulse of 72 /min, a respiratory rate of 18 /min, and a blood pressure of 120/70 mm Hg. Cardiac and respiratory assessments are unremarkable, and the abdominal exam is soft and non-tender. She displays normal function neurologically, and the pelvic exam yields normal results. Laboratory tests show:

Thyroid-stimulating hormone (TSH)                                            Normal

Human chorionic gonadotropin (β-hCG), Serum                       Normal