Another interesting study was that of Sahnounet al. (2017) who analyzed seminal samples from 73patients to investigate a cause of infertility; and they identified that humanspermatozoa have the Toll-like receptor 4, which reacts to bacteriallipopolysaccharide stimulation and results in production of reactive oxygen species.Oxidative stress results from a disproportion between the formation of reactiveoxygen species and the antioxidation system. Here, TLR4 is linked to Infertility.