The Research Of Follicle-stimulating Hormone Receptors Expression On Granulosa Cells With Poor Ovarian Response In IVF Cycles

BackgroundThe successful carry-out of the assistant reproduction technique, particularly the in vitro fertilization (IVF) technique, however, provides a bright prospect of treatment for the infertile young couples. With the development of 1VF techniques, controlled ovarian hyper-stimulation (COH) is widely utilized. It strengthens and improves ovarian function, and also helps produce more healthy oocytes to be fertilized and more embryos to be transferred so as to raise the pregnancy rate.Ovarian response to the exogenous gonadotropin is the pivotal step in IVF. However, Ovarian response to exogenous gonadotropins is individual differences, the same scheme and the same doses of gonadotropins, ovarian response each are not identical in individual patients, the poor ovarian response is approximately 9% - 24%.Several parameters have been postulated as predictors of the ovarian response,all of which strive to assess ovarian reserve,such as age,basal FSH,antral follicle count (AFC), ovarian volume, basal inhibinB, anti-mullerian hormone (AMH),P/E2 ratio and dynamics tests. Many reproductive centers conventionly assess ovarian reserve before controlled ovarian hyper-stimulation (COH).and adopt individual scheme, in order to get enough quantity and quality of oocytes. However, there exists a part of their patients; they occur unexceptedly poor ovarian response. What is mechanism? And how to deal with such patients is a great challenge for clinical work.The local regulating mechanisms exist in Ovarian, including follicular follicle-stimulating hormone (FSH) as many regulation systems, and FSH plays a central role in oogenesis.It triggers the maturation of follicles, the proliferation of granulosa cells, and induces synthesis of the androgen-converting enzyme aromatase.Furthermore, it plays a pivotal role in the recruitment of the dominant follicle. FSH action is mediated by the specific receptor (FSH receptor, FSHR). FSHR is a member of the family of G-protein-couple dreceptors expressed mainly in granulosa cells (GCs) of ovary and Sertoli cells of the testis. The expression of the FSHR is the crucial step in development of gonadal responsiveness to gonadotropin. Because of the important role of FSH in reproductive physiology, more and more attention has been paid to its corresponding receptor (FSHR). Several studies have been made to demonstrate that the changes of FSHR structure and function are responsible for the different ovarian responses to gonadotropin stimulation. FSHR genes mutations can cause ovarian response down even disappear. Some researches explore the relationship between the expression of FSHR and ovarian responsibility, but controversy. However, because lack of unified diagnostic criteria, the research results has uncomparability.Whether the FSHR level afects the IVF outcome was still unknown.ObjectiveThe purpose of the research is: (1) to investigate the relationship between FSHR expression on GCs and the poor ovarian response to gonadotropin stimulation in IVF cycles. (2) To investigate whether the FSHR expression is correlated with the IVF outcome. Materials and MethodsIVF-ET candidates were patients in the reproductive center of our hospital during October 2007 to June 2008.according to the predictor parameters of the ovarian response, every infertility patients is assessed before controlled ovarian hyper-stimulation (COH), then choosing the appropriate scheme. Poor ovarian response expectedly adopts GnRH-a"Flare up"short scheme, Normal ovarian response expectedly adopts GnRH-a standard long scheme. inclusion criteria of Poor ovarian response: (1) duration time of administered gonadotropins was more than 14 days for unexpectedly poor ovarian response; (2) oocytes acquired were more than five in bilateral ovary for expectedly poor ovarian response; (3) oocytes acquired were more than 10 and less than 20 and duration time of administered gonadotropins was less than 14 days for normal ovarian response. Exclusion criteria: endometriosis, autoimmune diseases, chromosome abnormality, endocrine or metabolic diseases, ovarian surgery or only one ovary. After oocyte retrieval, Granulosa cells were extracted from follicular fluid by Ficoll method, detecting expression of FSHR granulosa cell by immunohistochemical method, FSHR proteins semi-quantitative analysis is by Western-blotting, The total dosage and duration of ovarian stimulation with rFSH, number of oocytes retrieved,fertilize eggs,cleavage eggs,high quality embryos and the outcomes of pregnancy were recorded detailly. The rate of fertilization, cleavage, high quality embryo, implantation and pregnancy were calculated. All data were processed with SPSS 13.0 software for Windows.Results1. The unexpected poor ovarian responder is significant difference than the other two groups between the cumulative dose and duration time (P < 0.05), the average daily dosage was no more than the normal ovaries response (P > 0.05), but it is significant difference than the predicted poor ovaries responder. 2. Unexpectedly poor ovarian responder were no significant difference compared with normal group in oocyte retrived, oocyte and embryos quality, pregnancy rate (P > 0.05), but the predictedly poor ovarian responder were significant lower (P < 0.05).3. Three groups of granular cell FSHR expression, unexpected poor ovarian response group, its FSHR fluorescence intensity was similar with the group of normal ovarian response, but it is higher than predicted group.4. The FSHR protein content has difference in the three groups, there was no significant difference between the unexpected and normal group (P > 0.05), and it is higher than predicted group (P < 0.05).Conclusions1. To unexpectedly poor ovarian responder, we can be obtained similar oocytes and high-quailty embryos and pregnancy rate by extending duration of administered gonadotropins with normal ovaries response.2. Predictable poor ovarian responders due to ovarian dysfunction, the oocytes retived were decreased, even though prolongged duration time of administer, the rate of embryos and pregnancy was significantly lower.3. Unexpectedly poor ovarian responder is un-relevant with the FSHR protein content, but the FSHR protein expression is descend for the predictable poor ovarian responser.4. The FSHR protein expression on granulosa cells is positive correlation with the rate of high-quailty embryos and pregnancy.