There are two egg fertilization methods:

• Conventional insemination: the eggs and the sperm are put together in a dish with some little drops of medium culture
• Intracytoplasmic sperm injection or ICSI: a sperm is introduced into the egg. This is the technique used with a low sperm count and/or poor motility in order to ensure the fertilization.

Regardless of the method used not all the eggs may successfully be fertilized and produce embryos.

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