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Fertility Glossary

Metaphase I (MI)

An intermediate egg stage between GV and mature.

Embryology

MI eggs are partway through their final maturation. Some become mature (MII) after a few hours in the laboratory.

Also known as: MI, MI oocyte

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.

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