Considering the effective interventions without deleterious reproductive effects, GnRH-ant co-treatment (36 RCTs; OR 0.61, 95% C 0.51 to 0.72, n = 7,944; I2 = 31%) and GnRH agonist triggering (8 RCTs; OR 0.15, 95% CI 0.05 to 0.47, n = 989; I2 = 42%) emerged as the most effective interventions for preventing OHSS with a moderate CoE, even though elective embryo cryopreservation exhibited a low CoE. The gene discussed is GNRH1; the disease is ovarian hyperstimulation syndrome.