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Fertility Glossary

Assisted oocyte activation

A laboratory technique used after repeated fertilisation failure.

Eggs, sperm & embryos

Calcium ionophore exposure after ICSI can trigger the activation step that some eggs fail to complete. Evidence comes from small studies in selected couples, and it is not appropriate as a routine addition.

Also known as: AOA, calcium ionophore

Sources

  • ESHRE guidance (used where Canadian wording is unavailable)

Last reviewed: September 9, 2026. Written by the Antega Editorial Team. General information only โ€” always follow the advice of your own clinic, doctor or pharmacist.

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