Intrafollicular expression of matrix metalloproteinases and their inhibitors in normally ovulating women compared with patients undergoing in vitro fertilization treatment

Objective: To assess possible differences in the activity of matrix metalloproteinases (MMPs), MMP-2 and MMP-9, and their inhibitors, the tissue inhibitors of MMPs, TIMP-1 and TIMP-2, in follicular fluid (FF) of women undergoing in vitro fertilization (IVF) treatment and of normally ovulating women. Design: Prospective study. Methods: MMP-2 and MMP-9 activity was analyzed by gelatin zymography and MMP-2, MMP-9, TIMP-2. TIMP-1 and 17beta-estradiol levels were measured in FF by ELISA. Results: We found significantly reduced MMP levels in FF of women undergoing IVF treatment when compared with those of normally ovulating women. In contrast, the TIMP-1 levels were found significantly increased in FF from IVF patients vs normally ovulating women. No significant differences were found for TIMP-2 between the two groups. Conclusions: These findings underline a marked difference in MMPs and their inhibitors in the IVF women and the control group. Therefore we assume MMPs depend on hormonal steroidogenesis modulation induced by the gonadotropin protocol for IVF treatment.