GNRH1 and ovarian hyperstimulation syndrome: A previous study found that in fresh transplantation cycles of patients with PCOS, the number of oocytes retrieved (17.49 ± 7.17 vs. 12.85 ± 7.26) and the clinical pregnancy rate (53.92% vs. 40.00%) were significantly increased in EFLL compared with the GnRH antagonist protocol, and there was no significant difference in the incidence of OHSS [10].