A 28-year-old woman comes for treatment of hirsutism. She is obese and has facial acne and hirsutism on her face. Serum LH level is 32 mIU/mL and FSH is 9 mIU/mL. Androstenedione and testosterone levels are mildly elevated, but serum DHEAS is normal. The patient does not wish to conceive at this time. Which of the following is the most appropriate treatment of her condition?