INSIDEEMBRYO · FERTILITY GLOSSARY
Intracytoplasmic sperm injection, abbreviated ICSI, is an assisted fertilisation technique in which a single spermatozoon is introduced directly into the cytoplasm of a mature metaphase-II oocyte using micromanipulation. Prior to the procedure, cumulus and corona cells are generally removed to…
Intracytoplasmic sperm injection, abbreviated ICSI, is an assisted fertilisation technique in which a single spermatozoon is introduced directly into the cytoplasm of a mature metaphase-II oocyte using micromanipulation. Prior to the procedure, cumulus and corona cells are generally removed to permit assessment of oocyte nuclear maturity and controlled manipulation. ICSI bypasses several physiological steps of natural fertilisation, including sperm passage through the cumulus complex, zona pellucida penetration and conventional sperm–oolemma fusion. Direct sperm injection does not bypass the requirement for appropriate oocyte activation, completion of meiosis II and maternal and paternal pronuclear formation. Fertilisation following ICSI is subsequently assessed morphologically, with the presence of two pronuclei representing the classical appearance of normal fertilisation.
For education, not individual medical advice. Ask your fertility team about your care.