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Polycystic ovary syndrome (PCOS) features hyperandrogenism, oligo-ovulation/anovulation, and polycystic ovarian morphology; insulin resistance is common. For patients seeking pregnancy, the first-line ovulation induction agent is an aromatase inhibitor such as letrozole, which lowers estrogen synthesis and releases hypothalamic-pituitary negative feedback, increasing FSH secretion and promoting follicular development. Randomized trials demonstrate higher ovulation and live-birth rates with letrozole versus clomiphene in PCOS, particularly in patients with obesity. Metformin improves insulin sensitivity and can restore ovulation in some, but as monotherapy it is less effective for fertility than letrozole; it is useful adjunctively in metabolic syndrome or impaired glucose tolerance. Combined oral contraceptives and progestin IUDs regulate bleeding and protect the endometrium in anovulatory patients not attempting conception but suppress ovulation, counterproductive to current goals. Lifestyle modification (weight reduction, exercise) remains foundational, as modest weight loss can significantly improve ovulatory function and treatment success. Monitoring for multifollicular development and counseling about multiple gestation risk are appropriate during pharmacologic induction.