IMSI is when a sperm is placed under a high microscopic magnification is then selected. It allows the detailed examination of the sperm in a larger magnification under the microscope. In this way, the organelles or vacuoles in the head area of ​​the sperm are evaluated in more detail and the best quality sperm is selected and used to fertilise the egg. In standard microscopes, the sperm cell is grown approximately 400 times and under the IMSI program, the best sperm is selected with the help of special computer program. It is used especially in couples with sperm factor, better sperm means better fertilisation is achieved and embryo development.

The anomalies within the sperm head there are more effective anomalies on fertilization rate and healthy embryo development. As the number and morphology of the sperm decreases and the age of the male increases, the rate of anomalies in the sperm head increases. In this context, IMSI method allows us to obtain higher fertilization rate and more healthy pregnancy.

With IMSI, greater success is achieved in the following cases than in the standard ICSI method: