Clomiphene is given for 5 days following the onset of a spontaneous or a progestagen-induced period, starting any time from days 2, 3, 4, and 5; the recommended starting dose is 50 mg/day. Letrozole has been shown to have good ovulation rate in CC-resistant PCOS women; 5 mg/day showed an optimal result, with a high monofolliculogenesis rate in PCOS women. The approach to the treatment of PCOS patients with gonadotropins is the “step-up” protocol with no difference in efficacy between the different gonadotropin preparations. PCOS patients undergoing IVF treatment have similar pregnancy, miscarriage, and live birth rates compared to those of non-PCOS patients. Ovarian stimulation in women with PCOS poses a particular challenge, as many of these women exhibit exaggerated response, resulting in an increased risk of OHSS and multiple gestations. The transfer of frozen-thawed embryos has important implications for the management of women undergoing ovarian hyperstimulation for IVF. FET endometrial preparation by following stimulation with Letrozole combined with hMG in PCOS is a novel protocol; the clinical pregnancy rate was 51.1 % (256/501), implantation rate was 36.8 % (349/948), miscarriage rate was 18 % (46/256), and live birth rate was 41.9 %(210/501). 67.1 % (336/501) cycles developed only one leading follicle (≥14 mm), and two follicles ≥14 mm developed in 19.6 % (98/501) cycles. The protocol of Letrozole combined with hMG has the potential to be the first-line treatment option for ovulation induction in PCOS women, while its use in ovarian stimulation for IVF deserves further study.