Intracytoplasmic Sperm Injection (ICSI)
ICSI is specifically geared towards the treatment of male-factor infertility. Compared with conventional insemination where a defined concentration of sperm is co-incubated with the oocyte, the ICSI procedure manually introduces a single sperm into a single oocyte. The technique is advantageous in that it bypasses the physiological interactions normally necessary for sperm/egg interaction, which may be compromised in some samples. The procedure is performed in concert with an IVF cycle. The sperm injection process occurs on a specialized microscope, which permits direct visualization of the sperm, the egg and the introduction of the two gametes.
As with most innovative procedures, interest in the health of children conceived using ICSI surfaced along with its widespread use. Even though thousands of babies now have been born worldwide since its introduction, some studies show now that there is a slight increase in congenital defects following ICSI. However, some large-scale studies have refuted this evidence. Nonetheless, this evidence for increased incidence of defects may be related to the fact that pregnancy is now possible with sperm that naturally would never occur.