A 24-year-old unmarried woman from Delhi presents with amenorrhea for 8 months and progressive weight gain over 2 years. On examination: BMI 28 kg/m², hirsutism (Ferriman–Gallwey score 12), acne, and acanthosis nigricans. Pelvic ultrasound shows bilateral polycystic ovaries. Serum LH:FSH ratio is 3.2:1, fasting insulin 18 mIU/L, and fasting glucose 92 mg/dL. What is the most appropriate next step in management?