CA125 in culture medium of preimplantation embryo.

The first stage of the implantation is the adhesion of the embryonic pole of the blastocyst to the decidua. Such a phenomenon has been demonstrated to be dependent on the presence of glycoproteic compounds, produced partly by the decidua and partly by the embryo. CA125 is an antigenic determinant associated to a glycoprotein expressed by various embryonic tissues. The objective of our research has been to measure the production of CA125 by the embryo in the initial phase of its development. Patients were recruited from our in vitro fertilization program. The culture medium used for the oocytes and for the embryos was collected and CA125 levels were measured. The results indicate that there is not a statistically significative difference between the values of CA125 measured in the mediums where a pronucleus or an embryo was present and the negative controls. From our data, therefore, it can be concluded that CA125 expression begins later in the human embryonic development than 8-cells-stage embryo.