Depot versus daily administration of gonadotrophin releasing hormone agonist protocols for pituitary desensitization in assisted reproduction cycles.

Background: Gonadotrophin-releasing hormone agonist (GnRHa) has been widely used in cycles of in vitro fertilization (IVF). Among the various types of GnRHa ovarian stimulation protocols, the long protocol presents the best clinical pregnancy rates per cycle initiated (GnRHa administration until the suppression of ovarian activity is evident, within approximately 14 days). There are two types of GnRHa administration that can be used to lead to hypophysis desensitization in the IVF cycle in the long protocol: one consisting of daily GnRHa low doses, and another with the administration of analogues in higher long-acting doses (depot).