Intracytoplasmic sperm Injection (ICSI) is routinely used throughout the world as a fertilisation treatment. It is believed that around 60% of assisted conception cycles use ICSI with traditional IVF making up the rest. ICSI has been traditionally used to treat male factor infertility. A semen analysis is routinely undertaken during early investigations of infertility to find out where any problems may lie. A poor quality semen analysis would indicate that ICSI should be used as an aid to fertilisation.
During ICSI, a single sperm is picked up by the embryologist using a specialised piece of equipment called a micromanipulator. It is injected into the mature egg and left to fertilise. This procedure overcomes any problems the sperm has on motility (i.e. swimming to the egg) as well as potential morphological problems which would prevent it from normally penetrating the ‘shell’ around the egg called the zona pellucida.
This treatment was revolutionary in treating male factor infertility when first used in the early 90’s, but it is now also used much more widely in treatment cycles. It is now used where there was previous poor fertilisation rates using traditional IVF; unexplained infertility; and it is also being used where there is no indication of poor sperm quality at all. This is particularly so in clinics specialising in treating couples from overseas. Due to the cost involved in travelling abroad for IVF treatment, the worst case scenario initially would be for none of the eggs collected from a stimulated partner to be fertilised. To avoid this, overseas clinics will routinely suggest ICSI over traditional IVF.
With fertilisation rates for ICSI as good as or better than IVF and with no detrimental effects on pregnancy rates, the only obvious issue for couples would be the cost of ICSI. The training, equipment and time required to perform ICSI means that this treatment usually costs more than IVF. However, recently another concern has surfaced; the safety of ICSI as a technique has been questioned. A large historical study in Australia found a significant increase in abnormalities in babies conceived using ICSI compared to those conceived naturally. The study, published in the New England Journal of Medicine this year, looked at the rate of birth defects in children born after IVF and ICSI and compared it to those naturally conceived. Overall, there was a higher rate of defects reported in children born after using ICSI compared to IVF (9.9% v 7.2%). The rate of abnormalities in children conceived naturally was 5.8%. After adjustment for parental factors, the rate for IVF abnormalities was not significant whilst those for ICSI were. Whilst this is an important finding, it is worth bearing in mind that this study was based on historical data. Assisted reproductive technologies have got better and so the risk may now be reduced. In addition, it was not clear whether the increased rate of abnormalities observed were the result of using sperm from men which wouldn’t normally achieve fertilisation naturally and therefore would be more likely to pass on anomalies.
ICSI has helped thousands of couples who, in the past, wouldn’t have been able to have a child. Anyone concerned about using it as part of their treatment should talk to their fertility provider for reassurance.
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