IVF & treatment
In the long protocol, down-regulation with an agonist such as buserelin usually starts in the previous cycle's luteal phase, followed by stimulation injections.
Also known as: agonist protocol, long down-regulation protocol
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Sources
Last reviewed: 23 September 2026. Written by the Antega Editorial Team. General information only — always follow the advice of your own clinic, doctor or pharmacist.