In the context of endometriosis, altered intrafollicular levels of pro-inflammatory cytokines have been found in patients with moderate/severe disease undergoing IVF, compared to controls (with tubal factor infertility) and have also been related to the maturity of the developing oocyte: FF from follicles aspirated from endometriosis patients showed significantly higher concentrations of interleukin (IL)-8 and IL-12 compared to controls, whereas IL-8 and IL-12 levels were found to be lower in the FF of follicles containing a mature vs an immature oocyte. This evidence concerns the gene CXCL8 and Infertility.