Intra cytoplasmic sperm injection (ICSI)

What is ICSI?

ICSI is a treatment, which is used to treat patients with severe male factor infertility and for whom conventional IVF is inappropriate, has failed, or has produced very poor fertilisation previously. Its main advantage over routine IVF is that we only need one sperm to inject into each egg and therefore it is possible to achieve fertilisation in cases with severely reduced sperm counts, poor sperm motility, or low numbers of normally shaped sperm. It can also be used in cases where sperm has to be removed surgically from the testis, or when there are high numbers of anti-sperm antibodies present.

How is ICSI carried out?

ICSI was first introduced into clinical treatment in 1992. It involves injecting a single sperm directly into the centre of each egg. The fertilized egg can then be transferred into the womb of the woman as in a normal IVF cycle. ICSI is simply an additional step to routine IVF, performed in the laboratory. Before and after the ICSI procedure, treatment is identical to IVF therefore please read the information about IVF.

Are all the eggs injected and does injecting cause any damage?

After the egg collection, the eggs are prepared and assessed by the Embryologist. Only mature eggs will be suitable for injection, and not all the eggs collected will have reached the required maturity. Usually we will be able to inject at least 80% of the eggs collected.

The process of injecting the sperm does damage a small number of eggs (<10%). The damage usually becomes evident either during or after the procedure. Any eggs that are damaged in this way will not be used in the treatment.

Are there any other risks?*

Because ICSI is a fairly new treatment (it was introduced in 1992), it is not yet known whether there is any risk that injecting the sperm into an egg could damage it, with possible long-term consequences for the child.

The risks that have so far been associated with ICSI are:

• Certain genetic and developmental defects in a very small number of children born using this treatment. However, problems that have been linked with ICSI may have been caused by the underlying infertility, rather than the technique itself.
• The possibility that a boy conceived as a result of ICSI may inherit his father’s infertility. It is too early to know if this is the case, as the oldest boys born from ICSI are still in their early teens.
• An increased risk of miscarriage because the technique uses sperm that would not otherwise have been able to fertilise an egg.
• A low sperm count caused by genetic problems could be passed on to a male child, so you may want to undergo genetic tests before going ahead with ICSI. Infertile men with low sperm count or no sperm in their ejaculate may be tested for cystic fibrosis genes and for chromosome abnormalities. You may want to discuss the full implications of taking these tests with your clinician or the clinic’s counsellor before going ahead.
  *Information from the HFEA.

For more information, and if you have any queries, speak to your consultant.

Suitability

ICSI may be appropriate if you have:

• Previous failed fertilisation or low fertilisation rate with conventional IVF
• Reduced sperm concentration or quality
• High levels of antisperm antibodies (these occur when the body becomes sensitised to sperm, causing an immune system response that destroys the sperm).