Downregulation
Also written as down-reg
The temporary suppression of the pituitary gland's hormone signals using an agonist drug, done before starting stimulation in a long protocol cycle.
In plain English
It's the phase where medication quietens down your natural hormone cycle, so the clinic has full control once stimulation starts.
Why it matters
It can cause menopause-like side effects for a week or two, which many people aren't warned to expect.
Related terms
Guides that cover this
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