Lower growth factor expression in follicular fluid undergone in-vitro fertilization

Objective: This study was performed to identify whether growth and differentiation factor-9 (GDF-9) and transforming growth factor-${\beta}1$ (TGF-${\beta}1$) expressions would be lower in the follicular fluid (FF) of those over age 35 who underwent IVF than under age 35. Methods: A total of 24 IVF cycles (20 patients) were included in this study. All of patients were stimulated for IVF by the GnRH short protocol and divided into two groups for analysis, according to their age: <35 group (14 cycles, 11 patients) vs. ${\geq}35$ group (10 cycles, 9 patients). The expression levels of GDF-9 and TGF-${\beta}1$ were determined by western blotting and quantitative enzyme-linked immunosorbent assay. Results: The numbers of retrieved oocytes and metaphase II oocytes were significantly lower in the ${\geq}35$ group. Lower expression of GDF-9 and TGF-${\beta}1$ by western blotting in the ${\geq}35$ group were observed as well. The mean GDF-9 and TGF-${\beta}1$ levels by enzyme-linked immunosorbent assay were lower in the ${\geq}35$ group. The values were $6,850.5{\pm}928.4$ ng/L vs. $3,333.3{\pm}1,089.2$ ng/L of GDF-9 ($p$ <0.05) and $3,844.1{\pm}571.1$ ng/L vs. $2,187.7{\pm}754.0$ ng/L of TGF-${\beta}1$ ($p$ <0.05). A negative correlation between GDF-9 and age was observed (r=-0.546, $p$=0.006). Conclusion: GDF-9 and TGF-${\beta}1$ production from stimulated ovaries during IVF appears to decrease with age.