ICSI is Intra cytoplasmic sperm injection. This is a procedure in which a single motile sperm is injected into the egg. In this procedure, the eggs are studied, surrounding cells separated and the maturity of the egg is confirmed prior to injecting the egg with the sperm.
ICSI is often recommended if other problems with the sperm have been identified that:
Prevent sperm binding to the egg
Cause failure to fertilize or an unexpectedly low fertilization rate (below 20%)
Have been collected from the testicles or epididymis (TESA/PESA