Microfertilisation (ICSI)

In some cases, the normal fertilisation process described above is not possible because either the sperm is not motile enough or the sperm count is low, or because the egg zona pellucida is thickened.

In such cases it is possible to inject the sperm into the egg using microfertilisation. This technique is called Intra Cytoplasmic Sperm Injection (ΙCSI).

Initially, the oocytes after being "cleaned" from surrounding cells, are placed successively in a drop of culture medium and held in place by a holding pipette with the aid of a micro-manipulator. The sperm are placed in an adjacent droplet.

With the aid of a second micro-manipulator, sperm is aspirated through a very thin glass needle (injection pipette) and introduced into the oocyte. The oocytes are then placed in the incubator under culture conditions.

ICSI is essentially recommended when:

- the sperm contains spermatozoa without acrosome, i.e. deprived of the special enzyme that enables them to penetrate the oocyte;

- the sperm presents extensive agglutination of spermatozoa (immunological cause of subfertility: agglutination prevents sperm motility passively);

- the oocyte zona pellucida is thicker than normal;

- there has been failed attempt of in vitro fertilisation (IVF) with the classic method;

- in cases of severe oligoasthenozoospermia;

- low fertilisation rate in previous attempts;

- when there are ejaculation problems (in such case it is possible to use electrostimulation for sperm retrieval);

- when there is history