Intracytoplasmic sperm injection or ICSI is indicated to couples with poor sperm parametres and in cases of previous failed cycles or low fertilisation rates after classic IVF.
Couples go through the same procedure as with IVF, (ovulation induction and egg collection). The only thing that differs in a classic IVF cycle is the way of fertilization. With this procedure a single sperm is selected and injected into each of the eggs collected. One of the major advantages of ICSI is that very few sperm are required and the ability of the sperm to penetrate the egg is no longer important as it is bypassed by the whole technique. This makes it an excellent tool for cases where low sperm number, motility and morphology are present but also in cases where sperm has been retrieved surgically from the testis (TESE). The fertilised embryos are allowed to develop as for standard IVF treatment prior to embryo transfer
However, ICSI can only be carried out on mature eggs. Unfortunately, egg maturity can only be truly identified under the microscope and it is therefore possible that following egg collection, none of the eggs are suitable for ICSI. This situation is fortunately rare.
It is also important to remember that whilst ICSI is a technique used in the laboratory to help fertilisation to occur, it does not guarantee it. Furthermore, a small percentage of eggs will be damaged by the injection process and the damage is evident at the time of the injection procedure. These eggs can no longer be used.