Study On The Role Of PAPP-A And CRP In IVF-ET Therapy

Objectives: It is necessary for IVF-ET that obtains harvest high-quailty mature oocytes and keep internal environment of body which could be fit to implante embryo. After the pituitary was desensited by using gonadotropic releasing hormone-analog, ovarian microenvironment would become a main factor which effects information of high-quality oocyte. As a protease of IGFBP-4 in follicular fluid, PAPP-A could cleavages IGFBP-4, enhances IGFs bioactivity and regulates oocyte developing. If we used different clinical program of controlled ovarian stimulations and IVF-embryo transfers, It will emerge different clinical outcomes. The main reason may be different mechanism of gonadotropic releasing hormone-analog which cause the variance of ovarian miroenvironment. Nowadays, researchers gradually understand the whole COH is a state of systemic inflammation or potential systemic inflammation. CRP could active complement system and mononuclear phagocyte which produces IL-1 and IL-6．Because of stabilization of CRP and being cheaper in clinical detection, it is benefit to monitor the status of inflammation during COH.As a result, the purpose of the present study is to elucidate the expression of PAPP-A, CRP and their role in phase of harvesting mature oocyte and implanting embryo. It is also study that physiological functions of PAPP-A in oocyte maturation and selection of high-quality oocytes. Being detecting the level of CRP in blood-serum during whole therapy, our attempt is to determine a cutt-off value for CRP ratio which may serve as a predictive marker for the early phase of embryo implantation.Methods: (1) Detecting the expression of PAPP-A mRNA in granular cell and the protein level of PAPP-A in follicular fluid were measured with reverse transcription-polymerase chain reaction (RT-PCR) and enzyme linked immunosorbent assay(ELISA).(2) We collected serum of D₂-day, HCG-day, ET-day and detected the level of CRP by ELISA. The purpose is to know characteristic of inflammatory reaction during IVF-ET.Results: (1) The amount of mature oocytes was more, the expression of PAPP-A would be higher. The amount of mature oocytes kept positive relationship with the expression of PAPP-A, but negatively relationship with the level of LH. The expression of PAPP-A in pregnancy groups were higher than non-pregnancy groups.(2) The amount of mature oocytes were higher by using gonadotropin releasing hormone agonist short protocol group than gonadotropin releasing hormone antagonist flexible protocol group, but fine quality embryo ratio was lower than GnRH-anta flexible protocol. The expression of PAPP-A mRNA and level of PAPP-A was higher in GnRH-a short protocol group than GnRH-anta flexible protocol. It suggests that PAPP-A maybe took part in selection of follicular function and developing potentiality. Pregnancy ratio of GnRH-anta flexible protocol group was significantly higher than GnRH-a short protocol group. Although different protocol induced to form different ovarian microenvironment, but the outcome of clinic was identical. Two protocols can be used in clinical therapy. (3) No matter pregnancy group or non-pregnancy group, serum CRP level became more and more enhance during IVF-ET. Significant increasing of serum CRP was observed in non-pregnancy group. Cut-off value of CRP ratio could serve as a predictive marker for the early phase of embryo implantation.Conclusions: (1) PAPP-A has a key role in the course of oocyte maturation, and effects high-quailty mature oocytes selection. There was correlation between success of IVF-ET and PAPP-A level in some degree. Different protocol induced different ovarian miroenvironment which effect oocytes quality and potentiality. (2) CRP takes part in embryo implantation, which provides for monitoring clinical outcome.