Secretory endometrial and decidual proteins: studies and clinical significance of a maternally derived group of pregnancy-associated serum proteins.

In contrast to our ability to monitor placental function during pregnancy, due to the availability of a range of placentally derived secretory products such as HCG, HPL, SP1, PAPP-A, etc. the equivalent monitoring of the endometrial function in implantation and pregnancy has been impaired by a lack of equivalent endometrial products. Decidual diamine oxidase and prolactin have been extensively characterized but each have clinical drawbacks and may indeed be minor products of the endometrium. Recent developments in the characterization of the major secretory protein products of the endometrium, and a re-assessment of the origin of a number of placental proteins, radically alter our ability to monitor endometrial function, offer a new clinical window on pregnancy and might provide new knowledge on the extent of feto-maternal dialogue at implantation and during pregnancy. In this review, aspects of many scientific studies, and the function and possible clinical significance of these endometrial and decidual protein products are assessed.