Fertirelin is a synthetic luteinizing hormone-releasing hormone (LH-RH) analogue, and it is a potent LHRH agonist. After a transient increase, continuous administration results in downregulation of LH and FSH levels followed by a suppression of ovarian and testicular steroid biosynthesis.
Fertirelin was administered at the beginning of the protocol followed 7 days later by 500 μ G cloprosterol. Two days later, a second dose of fertirelin was given and AI performed 16-19 h later regardless of the incidence of behavioral oestrus. The conception rate did not differ between the 50 μ G fertirelin group (61.1%; N = 72) and the 100 μ G group.
