IntraCytoplasmic Sperm Injection
At CRM London we have extensive experience with ICSI (IntraCytoplasmic Sperm Injection). Indeed Robert Forman’s team was the first in the NHS to achieve a baby using ICSI in 1994. ICSI is used when the male partners’ sperm is suboptimal, when previous standard IVF treatment has been associated with a low fertilisation rate and occasionally used if only a few eggs are available. With ICSI a single motile sperm is isolated from the male partner’ sperm and the tail of the sperm is cut to immobilise the sperm. The sperm is aspirated into a very fine glass needle (about one tenth of the diameter of a human hair at its tip). The sperm is then injected directly into the centre of the egg and the needle withdrawn. The sperm is immobilised first because if it was to continue to move around inside the egg it could damage the delicate internal structures within the egg. Interestingly the fertilisation rate of eggs with ICSI even using “poor sperm” is higher than the fertilisation rate of eggs using standard IVF treatment with normal sperm. A very small percentage of eggs can be damaged by the injection procedure but this is more than offset by the increased fertilisation rate. Some people ask why we do not perform ICSI for all treatment cycles if the fertilisation results are better than with IVF and this is a valid point. In fact the main reasons are because we have more follow up with IVF babies (the first IVF baby was born in 1978, the first ICSI baby in 1993), ICSI is more invasive and also more expensive due to the equipment necessary and the additional highly skilled laboratory procedures that are required.
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CRM London ICSI PLUS
- + At CRM London we have a performance target that 75% of all mature eggs that we inject fertilise normally.
- + Our performance target for eggs that are damaged by the ICSI procedure is 4%. In fact we usually run at between 2-3%.
- + The eggs are very sensitive to temperature variations for the few minutes while they are out of the incubators for the ICSI procedures. Even though it may not affect egg fertilisation, a temperature drop of less than 2°C can damage the genetic structure of the egg leading to abnormal embryo development and miscarriage. At CRM London we keep a constant temperature throughout the injection procedure and we have Standard Operating Procedures to maintain temperatures of the eggs within the acceptable limits.








