Comparison of the Euploid Rate of Blastocyst Between PPOS and GnRH Antagonist Protocol in Women With PCOS Undergoing PGT-A

Inclusion Criteria: * Women age between 20 and 37 years. * Women diagnosed with PCOS according to the modified Rotterdam criteria: oligomenorrhea or amenorrhea, together with the presence of ≥12 antral follicles (≤9 mm) and/or ovarian volume \>10 mL on transvaginal ultrasonographic scanning, and/or clinical/ biochemical hyperandrogenism. Other causes of hyperandrogenism and ovulation dysfunction-including tumours, congenital adrenal hyperplasia, hyperprolactinaemia and thyroid dysfunction-were excluded Exclusion Criteria: * Presence of a functional ovarian cyst with E2\>100 pg/mL * Endometriosis grade 3 or higher * Repeated implantation failure (\>=4 embryos replaced or \>=2 blastocysts replaced without success) * Women with a uterine cavity abnormality, such as a uterine congenital malformation (uterus uni-cornate, bicornate, or duplex); untreated uterine septum, adenomyosis, submucous myoma, or endo-metrial polyp(s) * Women who are indicated and planned to undergo PGT-SR (Preimplantation genetic testing for structural rearrangement) or PGT-M (Preimplantation genetic testing for monogenic disorder), for example, parental abnormal karyo-type or diagnosed with monogenic disease; * Recipient of oocyte donation * Presence of hydrosalpinx which is not surgically treated