IL4 and endometriosis: Endometriosis is considered to be an inflammatory process in which activated immune-related cells secreted large amounts of cytokines.[12] These cytokines could attract more immune cells and promote growth of ectopic endometrial cells, contributing to the occurrence and development of endometriosis.[13,14] Previous studies have indicated a link between raised serum levels of IL-4 or IL-6 and endometriosis.[15,16]