Progesterone
A hormone that prepares and maintains the womb lining to support implantation and early pregnancy.
In plain English
It's the hormone that keeps your womb lining ready for and supportive of a pregnancy.
Why it matters
It's given as luteal phase support after transfer, often as pessaries, injections or gel, because IVF medications can affect the body's own natural production.
Related terms
Guides that cover this
Written by patients, not clinicians. This page has not yet been reviewed by a named fertility professional, so it explains published guidance and points you to the original source instead of giving medical advice. It is not medical advice. Decisions about your treatment belong with your own clinic. Read our editorial policy and corrections policy.