A Proof of Concept Study to Determine the Rise of Progesterone Levels After Human Chorionic Gonadotrophin (hCG) Trigger in Stimulated Cycles of IVF/ICSI

Studies have suggested that controlled ovarian hyperstimulation adversely affects endometrial receptivity. In ovarian stimulation cycles with exogenous gonadotrophins there is an ongoing debate regarding the effect of a late follicular phase progesterone level on reproductive outcomes. It is not yet clarified if an elevated serum progesterone level in the late follicular phase is a symptom or cause of an adverse effect on reproductive outcomes. A new hypothesis is evolving and gaining momentum providing a novel explanation for the association between late follicular phase progesterone rise and reproductive outcome. It is proposed that exogenous FSH (Follicle-stimulating hormone) administration results in supraphysiological levels of FSH, which induce an abundance of LH (luteinizing hormone) receptors on granulosa cells causing the follicles to become hypersensitive to LH-like activity (ie hCG trigger). Based on this hypothesis, the focus should be placed on the hCG trigger rather than on the late follicular phase progesterone rise.