A 28-year-old woman with PCOS (confirmed by Rotterdam criteria) presents with primary infertility for 2 years. She is anovulatory with normal BMI (22 kg/m²), no hirsutism, and normal androgen levels. Pelvic ultrasound confirms polycystic ovaries. She has been on lifestyle modification for 6 months without improvement in ovulation. What is the most appropriate next step in management?