The Influence Of Vascular Endothelial Growth Factor And Steroid Hormone Levels In Follicular Fluids On Oocyte Maturation And Fertilization

Objective To investigate the role of vascular endothelial growth factor (VEGF) and steroid hormones in follicular fluids on the maturity, fertility and diameter of oocytes during intracytoplasmic sperm injection (ICSI) cycles.Methods Follicular fluid was obtained from 105 follicles of 72 women undergoing ICSI-ET treatment. Estradiol (E2), progesterone(P) and testosterone (T) concentrations were determined by chemiluminesence immunoassay (CLIA), VEGF concentration was measured by enzyme-linked immunosorbent assay (ELISA) and oocyte diameter was measured by ultrasound machine. All the samples were grouped by the degree of maturity and the levels of steroid hormones and VEGF. The effect of VEGF, E2,P,T in follicular fluids on human oocyte maturation and fertilization was analyzed.Results The concentration of E2 is positively correlated with oocyte diameter (r=0.694, P<0.05), the concentration of P is positively correlated with oocyte diameter (r=0.856, P<0.05) and the concentration of T is negatively correlated with oocyte diameter (r=-0.785, P<0.05). The mean levels of E2 and P in mature group were higher than immature group, but no significant difference was found (P>0.05). T level in mature group was significantly lower than that in immature group.(P<0.05). In degenerate group, E2 level was significantly lower than that in mature group.(P<0.05). We find that the maturation rate (91.11%) is the highest when 10=P/E2=30(P<0.05), whereas the maturation rate was lower when P/E2<10 or P/E2>30. No significant difference was found for fertility rate among the three groups(P>0.05). The maturation rate was higher in group A than in group B(P<0.05). No significant difference was found for fertility rate between the two groups (P>0.05). In mature-oocyte group, VEGF concentration was higher than immature-oocyte group(P<0.05), but lower than postmaturity-oocyte group(P<0.05). The maturation rate and fertilization rate are the highest when 500=VEGF=650(P<0.05).Conclusion The oocyte diameter on the day of OPU is related to the maturity of oocytes. The intro-follicular steroid hormone levels on OPU are related to the corresponding maturation and degenerate of the oocyte. The level of VEGF and steroid hormones in follicular fluids can be taken as one of the reference indexes to quantitate the oocyte maturation and fertilization.