Intra-Cytoplasmic Sperm Injection (ICSI) is the most common method for assisted fertilization in IVF cycles. It involves the use of micromanipulators and exceptionally fine glass needles to pick up a single sperm cell and inject it inside a mature egg to achieve egg activation and fertilization.
When sperm counts are low, or the sperm does not have sufficient movement or it is abnormally shaped, fertilization may not be possible even in the test tube. In this case, the sperm is directly injected into an egg and this procedure is called Intra Cytoplasmic Sperm Injection (ICSI). ICSI brings success rates to the same levels with standard IVF in most cases of male infertility.
ICSI is labor intensive and requires highly skilled embryologists. ICSI is the method of choice for fertilizing eggs from couples with male-factor infertility. The male-factor infertility diagnosis includes low sperm count, low motility, poor morphology, or sperm samples recovered from testicular biopsy. ICSI is also used when there is previous failed fertilization from conventional IVF and is recommended for those undergoing genetic testing of their embryos.
We also prefer ICSI in fertility preservation cases to ensure that we do not experience an unexpected complete fertilization failure, since most fertility preservation patients will not have time to undergo a repeat cycle (as they are undergoing medical treatments that can affect their future fertility).