ICSI (intracytoplasmic sperm injection) is the process of injection of a spermatozoon into an oocyte with the help of a microinstrument. This method has been developed for treating difficult forms of masculine infertility, such as oligozoospermia, asthenozoospermia and teratozoospermia. But today the ICSI method is used much more often: when there is a small amount of spermatozoa in sperm, or if a small amount of oocytes has been obtained in the result of ovulation stimulation, or if fertilization hasn’t been achieved in the previous attempts at IVF. ICSI is also recommended for women over 40 years old who tend to have ocyte membrane thickening, so that spermatozoa don’t manage to fertilize it even in the case of normal findings.
How is the fertilization carried out in the process of ICSI?
The embryologist chooses the spermatozoon of the highest quality. Then he punctures the oocyte membrane and injects a spermatozoon directly into its cytoplasm with the help of micromanipulators and a special microscope. After that everything is carried out exactly like in the classic IVF process: the embryos are cultivated and in several days are transmitted into a female organism. The fertilization of all the oocytes obtained in the process of puncture is implemented under the same scheme.
The spermatozoa for the ICSI procedure can be obtained from ejaculate, or, in case there are none in the ejaculate (azoospermia), by puncturing the epididymis or tissue of testicles.