ICSI is the last resort for severe male factors including obstructive azoospermia (absence of sperms in semen), in which sperm may also be retrieved surgically from either the epididymis (PESA) or from the testes (TESA/ TESE/MESA). An azoospermic man can father a child provided sperm is retrieved from his testes.
The success rate differs for different types of sperm disorders.
After 17 to 20 hours, our laboratory staff will look for evidence of fertilization under the microscope. In our laboratory about 80% of oocytes (or female “eggs”) fertilize, but this figure is lower for patients with severe infertility factors. Sometimes fertilization does not occur despite “normal” looking eggs and sperm, even after the ICSI technique is used(In 2% of cases). The most common cause of failed fertilization is the inability of the sperm to penetrate the barriers that surround the egg or failure of sperm PN (Pronucleus) to decondense. It can also depend upon the egg quality. For the same man sperm quality may vary over time, and the same man can unexpectedly produce a semen sample of poor quality.