Laboratory and Ultrasound Findings and Response to Letrozole in PCOS Patients

The intervention in this study is ovulation induction using letrozole, an aromatase inhibitor commonly used in women with polycystic ovary syndrome (PCOS) to stimulate ovulation. Participants will receive letrozole at an initial dose of 2.5 mg/day for five days, starting on day 3 of the menstrual cycle. If ovulation is not achieved, the dose will be incrementally increased up to a maximum of 7.5 mg/day over a maximum of three cycles. Ovulation will be monitored through serial transvaginal ultrasounds to assess follicular development, and confirmed by measuring mid-luteal serum progesterone levels (\>3 ng/mL). Based on the response to letrozole, participants will be classified as either letrozole-sensitive (ovulatory) or letrozole-resistant (anovulatory) to identify potential predictors of resistance and improve individualized treatment strategies for PCOS-related infertility.