Background: Gonadotropin-releasing hormone (GnRH) plays essential roles in embryo
implantation, invasion of trophoblastic tissue, and steroid synthesis in the placenta.
Objective: The aim of this study was to evaluate the effect of GnRH antagonist administration  on pregnancy outcomes in early implantation period. Materials and Methods: In this  retrospective study, 94 infertile women undergoing GnRH antagonist protocol who were at  risk of ovarian hyperstimulation syndrome (OHSS) were included.