First the female patient’s eggs are harvested and kept in a laboratory environment and then outer layers of eggs are removed and mature cells are separated. The purpose here is to identify mature eggs to be used for microinjection. Then sperm from the male patient is prepared using several methods and one sperm is injected into each mature egg using a special micro-manipulation equipment. Then they are kept in special incubators with regulated conditions and checked every 24 hours. Eggs that are injected with sperms are stored in special liquids called media. For this procedure to be successful the couple need to be well prepared, and good embryology laboratory conditions and teamwork of a embryologist and nurses are needed.