Administration of Increased Dose of GnRH Antagonist for Coasting for Decreasing the Risk for Ovarian Hyperstimulation Syndrome( OHSS)

Coasting is one of the means to reduce the risk of OHSS for patients at risk for severe OHSS. During coasting gonadotrophin administration is withheld until serum E2 levels drop to a range considered safe. Prolonged coasting reduces the chance for implantation and pregnancy. The aim of the study is to explore whether an increased dose of GnRH Antagonist will shorten the coasting period without an adverse effect on cycle outcome.

30 patients undergoing IVF using a GnRH antagonist protocol that present with a high response to gonadotrophin stimulation, will be randomized into one of two groups: group A - withdrawal of gonadotrophin support and continue a daily dose of 0.25 mg of the GnRH antagonist. group B - withdrawal of gonadotrophin support and continue a double daily dose of 0.5 mg of the GnRH antagonist. The main outcome measures will be the duration of coasting (days)and the rate of serum E2 drop (%).