Isoenzymes of adenosine deaminase and metalloproteinases as biomarkers in in vitro fertilization and embryo transfer.

It is estimated that approximately 1 percent of babies born per year result from in vitro fertilization and embryo transfer, and other assisted reproductive technologies. In humans, the exact mechanisms that lead to embryonic attachment to the endometrial epithelium and invasion into the endometrial stroma have not been fully characterized. The aim of the study is to estimate serum total adenosine deaminase and isoenzymes ADA1, ADA2, as well as MMP-2, MMP-3, MMP-13 and MIP-1a as parameters for pregnancy following IVF-ET. The study group comprised seventeen women who conceived (Group A) and nineteen women aged 21-42 years who did not conceive (Group B) after IVF-ET. Blood samples were collected between 09.00 and 10.00 a.m. during IVF-ET treatment at two different periods. The first blood sample was collected before ET and the second sample 14 days after ET. All serum samples were assayed for the MMP-2, MMP-3 MMP-13 and MIP-1a concentrations with ELISA assay. Serum tADA activity was measured by a spectrophotometer using adenosine as the substrate (Method by Giusti). According to our results it was demonstrated that women who successfully conceived after IVF-ET showed significantly lower serum concentrations of ADA1, MMP-2, MMP-3 and higher serum concentration of MMP-13 at 14 days following ET. In conclusion, ADA1 may play a protective role at the hemochorial interface. Thus, our results suggest that ADA1 may have a modulatory role in the implantation and duration of the pregnancy. In women with successful or unsuccessful pregnancy compared with normal women the levels of ADA and MMPs may be affected by the exogenous hormone therapy according to the protocol of ovarian stimulation during IVF-ET.