GnRH Antagonist Protocol Enhances Coagulation During Controlled Ovarian Stimulation for IVF

Area of Science:

• Reproductive Endocrinology and Infertility
• Hemostasis and Thrombosis

Background:

• Controlled ovarian hyperstimulation (COH) may induce a hypercoagulable state in women.
• Different COH protocols, specifically long-acting GnRH-agonist (GnRH-a) and GnRH-antagonist (GnRH-ant), may differentially affect coagulation and fibrinolysis.

Purpose of the Study:

• To evaluate the impact of GnRH-a and GnRH-ant protocols on fibrin clot properties and thrombin generation.
• To compare changes in clot permeability, fibrinolysis efficiency, thrombin generation markers, and fibrinolysis inhibitors between the two COH protocols.

Main Methods:

• Prospective study involving 129 infertile women undergoing COH.
• Analysis of plasma fibrin clot properties (clot permeability [K_s]), fibrinolysis (clot lysis time [CLT]), thrombin generation markers (prothrombin fragments 1+2, endogenous thrombin potential [ETP]), and fibrinolysis inhibitor levels (PAI-1).
• Comparison of outcomes between GnRH-a and GnRH-ant protocols.

Main Results:

• The GnRH-ant protocol increased ETP and decreased K_s, indicating enhanced thrombin generation and reduced clot density.
• The GnRH-a protocol reduced thrombin generation (ETP, F1+2), increased K_s, reduced CLT, and decreased PAI-1 levels, suggesting improved fibrin clot properties and fibrinolysis.
• Compared to GnRH-a, the GnRH-ant protocol elevated PAI-1 levels, increased thrombin generation (ETP), and K_s.

Conclusions:

• The GnRH-ant protocol enhances thrombin generation and slightly decreases fibrin clot density.
• COH using the GnRH-a protocol demonstrates favorable effects by reducing thrombin generation and improving fibrin clot characteristics.
• Favorable post-COH clot permeability (K_s) was observed in women with positive pregnancy outcomes in the GnRH-a group.