GnRH antagonist
Also written as short protocol drug
A medication that quickly blocks the pituitary gland from releasing the hormone surge that triggers ovulation.
In plain English
It's a drug added partway through stimulation to stop you ovulating early, without the long build-up an agonist needs.
Why it matters
It's used in the 'antagonist protocol', a shorter route to egg collection with fewer injection days than the long protocol.
Related terms
Guides that cover this
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