Intracytoplasmic Sperm Injection
With ICSI, men with extremely low sperm counts can have fertilization and IVF success rates which match those of couples doing regular IVF with no male factor concerns. ICSI is also used in certain cases of unexplained infertility.
At a Glance
- ICSI is performed with male factor infertility or when using frozen sperm
- A single sperm is injected into the egg for fertilization
- Men with extremely low sperm counts can have fertilization and IVF success rates which match those of couples with other diagnoses
When is ICSI Used?
ICSI is commonly used in IVF, and when needed, is included in our fees. The male fertility testing guides us to know if it will be needed. Some of the factors ICSI helps overcome are:
- The man has low sperm count
- The sperm are not motile (do not “swim”)
- The sperm morphology, or shape, is not normal
- A male reproductive tract blockage
- Unexplained infertility
How ICSI Works
In cases of frozen sperm or low sperm characteristics, the fertilization may fail when IVF is done. In these cases, intracytoplasmic sperm injection (ICSI) is commonly a component of IVF. A single sperm is injected through the zona pellucida, the thin transparent layer surrounding the egg, directly into the egg in order to enhance fertilization. This precision technique involves selecting a single sperm with a tiny needle and removing the tail, making it immobile, to protect the egg. Then a micro-manipulation device holds the egg, which is only 80 microns in size (approximately half the size of the period at the end of this sentence), and then injects the single sperm head into the egg. When this is carried out, the success rate is excellent, and fertilization can be just as good as with normal sperm. This has enabled many men to overcome infertility. The safety of ICSI has been confirmed by a number of studies.
With ICSI, men with extremely low sperm counts can have fertilization and IVF success rates which match those of couples doing IVF with no male factor concerns and without ICSI.
Occasionally an egg is damaged by the ICSI procedure, but this is uncommon. The long-term net effects of ICSI are quite safe. There are some studies that show a population of babies after ICSI has a slightly higher incidence of birth defects. However, this is a skewed population involving men with male factor, some of whom may have inherent chromosomal or genetic defects themselves. It is difficult to determine if the defect is rarely caused by the procedure or if the sperm in male factor situation is the source of the defect.