Any IVF (in vitro fertilization) treatment procedure carries risks. ICSI (intra-cytoplasmic sperm injection), being a very delicate and difficult IVF procedure, does carry an even higher risk of failure. Normally during an IVF treatment programme the males sperm are subjected to rigorous procedures to establish their maturity and suitability for the procedure. In an ICSI procedure because the number of viable sperm available can be so low they are not subjected to a rigorous programme of testing. The risk of an abnormal sperm being injected into the ovum is, therefore, raised. In a standard IVF treatment there is an element of ‘natural selection’ as to which sperm fertilizes the egg. When the ICSI technique is used the choice of sperm available for fertilization is inevitably small.
~ Defects in the male ‘Y’ chromosome occur in about 5% of males that have been tested. This manifests itself in either a very poor quality of sperm or even an absence of them.
~ Klienfelter syndrome, this is ten times more likely to occur in a male that is infertile compared to fertile ones, it is due to an excess of X chromosomes. Chromosomes store the genetic make-up of our bodies. The sex chromosomes of our bodies are commonly referred to as X & Y. A male has an X and a Y chromosome. A female has two X chromosomes. Klienfelters syndrome is when a male has one Y chromosome but has more than one X chromosome.
~ Androgen receptor gene defects which usually occurs as a gene mutation giving rise to sexual differentiation disorders.
~ Cystic Fibrosis, a known hereditary disease that often results in male infertility.
Whilst studies are still in progress it is believed that the incidence of male infertility as a birth defect is twice as likely to occur in a baby born as a result of an ICSI procedure, as one that is not. ie 7.4% compared to 3.8%. There is also an increased risk of mental development being delayed slightly. Sexual chromosome abnormality disorders such as Klienfelter syndrome and Turner’s syndrome (where only one X chromosome is present in a female) is also increased from 0.5% for the general population to 1.2% for a birth following ICSI treatment.
However, the abnormality is unlikely to be due to the ICSI treatment itself, but more the poor quality of sperm, and the genetic make-up it carries, that is used to fertilize the ovum. ie defects in the father’s sperm are passed on to the off-spring.
What are presently only anecdotal reports seem to indicate that ICSI procedure could increase the number of occurrences of Prader Willi syndrome ( a genetic disorder usually treated with growth hormones) and the Anglemen syndrome (a neurological disorder leading to learning difficulties).
It would be both logical and proper for a couple to be offered and to accept counselling and screening for the above disorders prior to the commencement of an ICSI programme of treatment. At least then they will have done all they can to minimise the risks described above. If a genetic abnormality is identified, they should be offered or seek genetic counselling. They will then be able to evaluate the risk(s) of passing a genetic abnormality to their offspring. Following a successful birth arising from an ICSI procedure, the parents should consider having antenatal screening for congenital disorders.