PSG2 is a secreted protein that in humans is encoded by the PSG2 gene. It is a member of the human pregnancy-specific glycoproteins (PSGs) family. These proteins are synthesized in large amounts by placental trophoblasts and released into the maternal circulation during pregnancy. PSG2 consist of a single N domain, with structural similarity to the immunoglobulin variable domains, followed by a variable number of immunoglobulin constant-like A and/or B domains. It has an arg-gly-asp (RGD) motif, which has been shown to function as an adhesion recognition signal for several integrins, in the N-terminal domain.