Intracytoplasmic Sperm Injection (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 fertilization 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.
How is ICSI different IVF?
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 / unobstructive 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 fertilized.
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 micro-manipulation or ICSI.
One carefully selected sperm is injected into each selected egg using a micro-manipulator under high magnification microscope. Later the fertilized eggs are placed in the incubator and allowed to grow.
Who benefits from ICSI? Who are potential candidates for ICSI?
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 fertilize the egg
- In patients with recurrent fertilization failure with IVF
- In patients undergoing preimplantation genetic diagnosis
What are various risks associated with ICSI?
ICSI revolutionized 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.
What is IMSI?
IMSI is an advanced laboratory technique used to select sperms for fertilization. It is a real time method where sperms are selected under very high magnification ( around 6000 times) which is much higher than the standard 400 times magnification high is used in ICSI,.
With this magnification the morphology of sperms can be better seen so selecting the sperms with better morphology can improve the embryo quality and decrease the likelihood of failure and the likelihood of miscarriage.
What are the advantages of IMSI?
This technique is found to be useful in cases with recurrent IVF failure and in patients with poor morphology of sperms.