ICSI is now a well-established microinjection technique which has helped thousands of infertile men to overcome issues with sperm parameters. It is also useful in cases of fertilisation failures with repeated IVF cycles. The technique evolved in 1990’s in Belgium and since then has become established as one of the biggest discoveries in the management of infertility. Presently more than 50% cycles in India and up to 63% cycles in USA are ICSI cycles.
ICSI is mainly an embryological process. The process of ovarian stimulation, egg retrieval and embryo transfer remains the same as in IVF (described above). The male partner provides a semen sample on the same day by masturbation. Alternatively, sperms retrieved surgically from testis (in case of obstructive / un-obstructive azoospermia) or sperm that has been previously cryopreserved can also be used. So, technically the number of sperms required is only as many as the number of eggs that can be fertilised.
The eggs are also processed differently for ICSI, as they are first cleaned in order to clean them and remove the debris and outer cumulus cells. The eggs are screened for maturity under a microscope and the mature ones are selected for micromanipulation or ICSI.
One carefully selected sperm is injected into each selected egg using a micromanipulator under high magnification microscope. Later the fertilised eggs are placed in the incubator and allowed to grow.
- ICSI benefits all mainly men with low sperm count , poor motility or morphology
- In cases with surgically retrieved sperms like MESA, TESA, TESE, where this is the only tool to fertilise the egg.
- In pts with recurrent fertilisation failure with IVF.
- In patients undergoing preimplantation genetic diagnosis.
ICSI revolutionised the treatment of male factor infertility enabling even males with nil sperm count to father their own genetic child. It is a fairly safe procedure. But, some studies have indicated a marginal increase in risk of congenital malformations in the offspring (6 per thousand births compared to 2 per thousand births in general population). But it still remains to be proven if the real cause of the higher incidence of congenital malformations in such children is ICSI or just a transmission of genetic abnormalities from the male with severe sperm abnormalities.