Treatment add-ons
Usually using a calcium ionophore, it may be considered after previous fertilisation failure. The HFEA reviews the evidence for add-ons and publishes a rating for each; see the HFEA add-ons page for the current rating, as evidence can change.
Also known as: AOA, calcium ionophore, artificial oocyte activation
Related United Kingdom guides
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.