Is ICSI safe?
In addition to the risks associated with the standard IVF treatment, there is some concern about the safety of the ICSI procedure. This is mainly because of the risk of injecting an abnormal sperm since ICSI bypasses the natural stages of sperm maturation and selection. It is also possible that ICSI may result in fertilization of an abnormal egg (during natural or standard IVF a natural selection process is in action and it is less likely for an abnormal egg to be fertilized successfully).
Research has so far shown that there is an association between male infertility and the following disorders:
- Defects in the genes on the Y chromosome which are involved in the regulation of sperm production “Y chromosome micro-deletion” (the male chromosome) occurs in about 5% of males tested.
- Abnormalities in the number or structure of chromosomes e.g. Klienfelter syndrome (10 times higher than normal population) and translocation.
- Cystic fibrosis.
- Androgen receptor gene defects. Since the gene is on the X chromosome the daughters of men who become fathers by ICSI will eventually carry such defects and the sons of these women would have a fifty percent chance of being affected.
There are over 26,000 babies already born as a result of ICSI treatment worldwide. In general, the available data are broadly reassuring for the short-term health of ICSI babies but no information as yet available on long-term health.
It has been suggested that the rate of major birth defects may be as twice as high as in the background population (7.4% vs.3.8%). There may also be a slightly increased risk of mildly delayed mental development. There is a slight increased of sex chromosome abnormalities such as Turner's syndrome and Klinefelters syndrome (1.2% vs. 0.5% in the general population). There is no apparent reason to suspect that ICSI technique is itself harmful (not a procedure related). It is possible that the genetic disorders, which have led to the sperm problem in the father's sperm, may be passed on to the offspring.
There is anecdotal reports that ICSI may increase the incidence of syndromes associated with aberrant genetic imprinting, such conditions include Prader-Willi and Angelman syndromes.
Before a couple considers treatment with ICSI, they should be offered counseling and screening for the above disorders with the exception of vasectomy cases. When a genetic abnormality is identified the couple should undergo genetic counseling before proceeding with treatment and should be made fully aware of the risk of transmission of the abnormality to the offspring.
It is clear that careful follow up of the children born after ICSI is important and patients who conceive by ICSI should carefully consider antenatal screening tests such as chorionic villus sampling or amniocentesis.