ICSI ( pronounced "eek-see" ) stands for Intra Cytoplasmic Sperm Injection, or micro injection is the most cost-effective treatment for male factor infertility.

Intracytoplasmic sperm injection (ICSI) can be used to fertilise eggs when your doctor thinks there is a decreased chance of fertilisation occurring with conventional IVF, either because of problems with low sperm numbers or low sperm motility, or because of other barriers to the fertilisation process such as sperm antibodies or previous failure to fertilise through IVF. 

A single sperm is injected into each egg. The sperm is selected mainly on the basis of its normal shape and size.