The present result clearly showed that the concentrations of a cytotoxic cytokine (TNFα) and oxidative stress (8-OHdG) in follicular fluids were significantly lower in the ultralong GnRHa therapy group than in the control group, suggesting a potential mechanism that additional GnRHa treatment before IVF-ET improves the pregnancy outcome of IVF-ET by reducing the detrimental effects of cytotoxic cytokines and oxidative stress in the peritoneal environment or implantation environment in patients with endometriosis. The gene discussed is TNF; the disease is endometriosis.