الفهرس 
Introduction and Aim of the workOnly 14 pages are availabe for public view
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Abstract
Infertility, defined by the World Health Organization (WHO) as the failure to conceive after one year of unprotected intercourse, is a frequent problem that affects 10-15 percent of couples in both developed and developing nations. Infertility is a serious health issue that affects an estimated 48.5 million couples globally. Intracytoplasmic sperm injection (ICSI) is a specialized form of in vitro fertilization (IVF) and is used as a gold standard technique for the treatment of severe male factor infertility. During this technique, physiologic selection barriers at fertilization are by passed, a single viable spermatozoon, preferably of good morphology is selected and injected into an mature oocyte . The principle techniques of sperm preparation consist of migration, density gradient centrifugation and filtration techniques. While for the migration the method is based on movement of the spermatozoa, for density gradient centrifugation and filtration techniques the method is based on a combination of the motility and the retention at phase borders and adherence to filtration matrices, respectively.