This study aims to determine serum concentrations of IL-6 and IL-16 in women with endometriosis and investigate whether the genetic polymorphisms of Interleukin 6 (rs1800795G/C) and 16 (rs4072111C/T, rs11556218T/G, rs4778889T/C) are associated with endometriosis and endometriosis-related symptoms in Nigerian women. The gene discussed is IL6; the disease is endometriosis.