Embryology
A mature, metaphase II egg has completed the division needed to accept a sperm. Only mature eggs can be injected in ICSI. Not every follicle yields an egg and not every egg is mature, which is why the number of follicles seen on scan is always higher than the number of usable eggs.
Also known as: MII egg, metaphase II
Sources
- European Society of Human Reproduction and Embryology (eshre.eu)
Last reviewed: 10 September 2026. Written by the Antega Editorial Team. General information only — always follow the advice of your own clinic, doctor or pharmacist.