Such a mysterious and beautiful process as fertilization, to great happiness, fell to the lot of embryologists. One of the fertilization techniques is called ICSI (intracytoplasmic sperm injection). Before starting this procedure, on the day of the puncture, the embryologist very carefully looks for the eggs under a microscope and puts them in an incubator for several hours. Then, after a while, it begins to cleanse the oocytes from the oocytcumulus complex and select mature cells, as evidenced by the presence of a polar body in the perivitilin space.
The next stage is the preparation of seminal fluid for fertilization. To do this, you can use the Swim up method or the gradient method. The sacrament of fertilization in the embryological laboratory takes place under a microscope under high magnification. The task of the embryologist is to select a morphologically correct and viable spermatozoon after careful examination under a high magnification microscope. The main selection criteria are:
- mobility (the sperm moves in a straight line at a speed of 25 microns / sec and more)
morphology (the sperm must have a correct and proportional structure);
- Then the embryologist proceeds to fertilization. Everything happens in microdroplets of a special environment, where the eggs are already waiting for this hour.
The procedure takes place in 4 stages:
- Sperm immobilization – the sperm is immobilized by rubbing the tail with a needle;
- Spermatozoa are aspirated into the thinnest needle, with the help of which the oocyte’s zona is punctured;
- Fixation of the oocyte on the suction cup;
- Oocyte puncture and sperm injection.