Intra-Cytoplasmic Sperm Injection - A treatment for fertilisation problems

Intra-Cytoplasmic Sperm Injection (ICSI) is a specialised laboratory technique that has revolutionised treatment for fertilisation problems, and in particular, male factor infertility, since its introduction in 1992.

What is ICSI?

ICSI stands for intra-cytoplasmic sperm injection, and it describes the process of selecting a sperm in the laboratory and injecting it directly into the egg. This differs from standard IVF, where the sperm is simply left in a petri dish with the egg to fertilise naturally. The major advantage of this technique is that as long as some sperm is collected (even in very low quantities), fertilisation is possible.

What are the advantages of ICSI?

  • Fertilisation is possible even with very low numbers of sperm.
  • The treatment is effective for several different types of sperm problems.
  • It may be useful whether there is a suspicion of a fertilisation problem, for example due to prior or increased risk of abnormal fertilisation or due to older age of eggs.
  • Although we cannot guarantee fertilisation, ICSI has a fertilisation rate of around 70%.
  • It is a widely used technique.

Who is suitable for this treatment?

This treatment is particularly suitable for couples with a male factor infertility problem. This can be related to the density, morphology or mobility of sperm. The treatment can also be used where there is a suspicion that there may be an issue with fertilisation.  

The ICSI Procedure

The ICSI procedure is performed in the lab, after the egg collection. ICSI involves the injection of a single sperm into the fluid contents of the egg cell, called cytoplasm. A glass pipette, which is finer than a human hair, is used to collect a single sperm and inject it into the egg. The fertilised embryo(s) is then transferred to the women’s womb. Other than this element in the lab, your experience of treatment is the same as that of patients undergoing IVF.

Dr Martin Wilding
Laboratory Manager St Paul's

Dr Martin Wilding

Martin Wilding has a degree in Biochemistry from Imperial College London and a Ph.D. in the physiology of fertilisation from University College London. He has practised IVF and ICSI from 1999 a....