Gonadotropin-Releasing Hormone(GnRH)
hormoneDefinition
A hormone released by the hypothalamus that signals the pituitary to release FSH and LH. Agonists and antagonists of GnRH are central to IVF protocols.
In IVF Treatment
GnRH agonists (like Lupron) initially stimulate then suppress the pituitary, preventing premature ovulation. GnRH antagonists (Cetrotide, Ganirelix) directly block GnRH receptors for more immediate suppression. Your protocol type determines which is used.
Frequently Asked Questions
What is the difference between a GnRH agonist and antagonist?
Agonists (Lupron) initially stimulate then downregulate the pituitary over 2-4 weeks. Antagonists (Cetrotide, Ganirelix) block GnRH receptors immediately and are added mid-stimulation. Both prevent premature ovulation.