Review Question - QID 215205

A 35-year-old woman presents to the clinic with milky nipple discharge that began 2 weeks ago. For the past 6 months, she has experienced vaginal dryness, painful intercourse, and no menstrual periods. She previously had regular periods since menarche at age 13. A review of systems is also notable for an unintentional 15-pound weight gain, dry skin, and fatigue that began 6 months ago. Her medical problems include depression for which she takes bupropion. She does not smoke or drink alcohol. The patient’s temperature is 96.5°F (35.8°C), blood pressure is 134/80 mmHg, pulse is 62/min, and respirations are 16/min. Physical examination is notable for mild facial edema. No visual field deficits are noted. A urine pregnancy test is negative. Serum thyroid-stimulating hormone (TSH) concentration is 7.2 µU/mL. Which of the following is the most likely cause of her milky nipple discharge?