A preliminary selection of sperm is carried out under a microscope 15 times more powerful than usual.
With this microscope we can see the internal morphology of the sperm and discard those with abnormalities.
According to the WHO a mature sperm should ideally have an oval head shape that is 4-5 microns long and 2.5-3.5 microns wide.
1 to 3 spermatozoa are selected and placed in a thin catheter and then inserted deep inside the uterus by the gynaecologist.
The Intra Cytoplasmic Sperm Injection selected, better known as IMSI for its acronym in English (Intracytoplasmic morphologically-selected sperm injection) is a laboratory technique used in IVF treatments (IVF) and involves inserting sperm into the egg.
IMSI is a real-time method where sperm is selected before the microinjection takes place. This is done using an inverted microscope that is able to provide much greater magnifying power (around 6000 times) than that normally used in reproductive laboratories (400 times) to carry out ICSI.
With this microscope, Biologists can see the internal morphology of sperm and discard those with abnormalities. Being able to select sperm without morphological alterations is believed to increase the chances of successful implantation of the pre-embryo and decrease the likelihood of miscarriage.
This technique still requires more study to demonstrate its efficacy and validity in order to be used routinely in the assisted reproduction laboratory and to be recommended with sufficient scientific evidence.
IMSI may improve the chances of fertilisation in vitro and can be used if you have performed several unsuccessful In Vitro Fertilization attempts.