Intra-Cytoplasmic Sperm Injection (ICSI)


Intra-cytoplasmic sperm injection (ICSI) is a microscopic procedure that involves the injection of a single sperm into a woman’s egg. ICSI may increase the rate of fertilization for some couples undergoing In-Vitro Fertilization.

Couples may benefit from ICSI in the following situations:

  • The male’s sperm count is low, the sperm have low or poor motility (percent moving or quality of movement) or if there is poor morphology (sperm shape defects)
  • When using frozen sperm, including donor sperm, because thawed sperm have a lower fertilization rate
  • Women whose eggs have a thicker than normal or hardened Zona Pellucida (the outermost membrane that surrounds the egg) making the egg more difficult for sperm to penetrate
  • Couples suffering from prior fertilization failure or other fertilization defects
  • As a precaution against unexpected fertilization failure
  • When preimplantation genetic testing (PGS or PGD) is performed to avoid contamination from other sperm on the egg surface.

When eggs are retrieved from a woman’s ovaries, both fully mature and immature eggs are usually obtained. It is not possible to determine in advance, what proportion of the eggs will be mature. The maturity of an egg is determined in the laboratory following its retrieval. Only mature eggs can be fertilized using the technique of ICSI. However, using ICSI does not guarantee successful fertilization of some or all the mature eggs obtained.

ICSI is performed by skilled and experienced embryologists in the CReATe IVF laboratory. Despite ideal conditions, ICSI may infrequently result in damage to an egg leading to its degeneration.

There is no evidence to indicate the ICSI procedure itself, results in any increase in congenital, physical or genetic abnormalities in excess of the expected (age-matched) incidence in children born of naturally conceived pregnancies.

However, if there is an underlying genetic reason for a male’s low sperm count, low motility or sperm defects, this trait may be inherited by any children conceived from that sperm. Under these circumstances, the transmission of a birth defect is caused by the man’s underlying genetic issue not by the use of ICSI to facilitate fertilization. For men with severe sperm abnormalities, genetic testing will usually be recommended before IVF with ICSI is performed.