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Fertility Glossary

Immature oocyte

An egg not yet ready to be fertilised.

Embryology

Immature eggs are at the germinal vesicle or metaphase I stage. They are usually not suitable for fertilisation, although some may mature in the laboratory.

Also known as: immature egg

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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