THE INFLUENCE OF HYPERESTROGENISM DURING IN-VITRO FERTILIZATION ON THE FIBRINOLYTIC MECHANISM

Objective-To evaluate levels of various fibrinolytic factor antigens i n women during ovulation induction using controlled ovarian hyperstimu lation. Methods-Plasma tissue-type plasminogen activator (tPA), urokin ase-type plasminogen activator (uPA), and the plasminogen activator in hibitors (PAI-1 and PAI-2) were evaluated and compared with plasma 17 beta-estradiol levels, ranging from 20 pg/mL to >5,000 pg/mL during th e course of treatment. Sixteen patients undergoing NF were compared pr ior to (controls) and following treatment with leuprolide acetate down -regulation followed by menopausal gonadotropin-CG ovulation induction for 14 days. Results-A significant positive correlation was found bet ween tPA and PAI-1 during treatment, while tPA and PAI-I were negative ly correlated with estradiol levels. Mean levels of tPA and PAI-1 sign ificantly decreased as estradiol levels increased. Conclusions-As the plasminogen activator decreased with increasing estradiol levels, this suggests a potential for thrombosis. However, the major plasminogen a ctivator inhibitor (PAI-1) also decreased; thus, the net clinical effe ct in terms of increased potential for thrombosis should be minimal. F urthermore, the levels of both tl?A and uPA were still within normal r anges. The overall data from this study suggest that ovarian hyperstim ulation with fertility-enhancing drugs does not enhance the potential for thrombosis even though there are elevated 17 beta-estradiol levels .