Intracytoplasmic Sperm Injection (ICSI)
In vitro fertilisation (IVF) has been used for many years to treat infertility. Success rates, however, have remained low in severe male factor cases, (poor sperm count or poor sperm movement) where the sperm are unable to penetrate the outer shell (zona pellucida) of the egg and therefore fertilisation does not occur. In recent years a number of techniques have been developed to try and address this problem.
One of these methods is called intracytoplasmic sperm injection or ICSI. This technique involves injecting a single sperm through the zona pellucida and into the centre of the egg (cytoplasm). The process is carried out under a microscope, using a very fine needle.
ICSI is suitable in any of the following cases:
- Previous failed fertilisation of eggs during conventional IVF.
- Previous low fertilisation rate during conventional IVF.
- Poor sperm parameters, e.g. low numbers of sperm, low numbers of motile sperm, poor forward progression of sperm.
The current average fertilisation rate using the ICSI procedure is 70%.
There is not yet any clear evidence whether ICSI results in higher rates of birth defects. The number of babies reported to have major birth defects, such as cleft palate, is between 1 and 5% in both the general population and in babies born following ICSI. Studies suggest that minor abnormalities occur in up to 20% of ICSI babies, compared to up to 15% of the population. More studies are needed in order to gain further insight into these possible effects.
It should also be understood that where the male partner is a carrier of the Y-chromosome deletion then any male offspring will automatically carry the same deletion and consequently will also be infertile. It is estimated that up to 6% of patients with severe male factor infertility have a Y chromosome deletion. If the male partner also has a chromosome abnormality then there is an increased risk of both miscarriage and chromosome abnormality in any offspring. The incidence of the male partner carrying a chromosome abnormality is in the region of 10 - 12%. We offer screening for the Y-chromosome deletion and chromosome abnormality for the male partner prior to starting treatment.
If you have any questions about ICSI, or any other aspect of your treatment please do not hesitate to contact one of the clinical staff.
There is not yet any clear evidence whether ICSI results in higher rates of birth defects. The number of babies reported to have major birth defects, such as cleft palate, is between 1 and 5% in both the general population and in babies born following ICSI. Studies suggest that minor abnormalities occur in up to 20% of ICSI babies, compared to up to 15% of the population. More studies are needed in order to gain further insight into these possible effects.
It should also be understood that where the male partner is a carrier of the Y-chromosome deletion then any male offspring will automatically carry the same deletion and consequently will also be infertile. It is estimated that up to 6% of patients with severe male factor infertility have a Y chromosome deletion. If the male partner also has a chromosome abnormality then there is an increased risk of both miscarriage and chromosome abnormality in any offspring. The incidence of the male partner carrying a chromosome abnormality is in the region of 10 - 12%. We offer screening for the Y-chromosome deletion and chromosome abnormality for the male partner prior to starting treatment.
If you have any questions about ICSI, or any other aspect of your treatment please do not hesitate to contact one of the clinical staff.
Should a Chromosome Analysis reveal a chromosomal abnormality you will be offered appropriate counselling.
