The infertility treatment, ICSI, is a method of assisted fertilization which was originally used in cases where a man has a very low sperm count or poor sperm motility (movement). With standard IVF, approximately 100,000 sperm are put in with each egg and placed overnight in an incubator where the hope is that one sperm will fertilize each egg. With ICSI, a single sperm is injected directly into the egg. As time has passed, the use of ICSI has greatly increased so that now the majority of IVF cycles involve ICSI, even if no sperm problems appear to be present.