sHLA-G has an important role in the activation of natural killer (NK) cells,Moreover, some authors associated sHLA-G in patients with endometriosis (mainly, themore severe forms) and adenomyosis (Hunt etal., 2000; Wang et al.,2008; Rached et al., 2019).However, the literature is completely absent in terms of the role of sHLA-G ininfertile patients with endometriosis and the concentration of this molecule in thefollicular fluid during controlled ovarian stimulation for IVF in this group ofwomen. The gene discussed is HLA-G; the disease is endometriosis.