What is ICSI (Microinjection) and what is the difference between IVF and ICSI?
Microinjection (or Intracytoplasmic Sperm Aspiration (ICSI)) is an IVF procedure in that fertilization takes place outside the body like in IVF. In conventional IVF, collected eggs are placed in a petri dish together with 100-150,000 washed sperm per egg. They are then placed in an incubator mimicking the uterine environment (gas, humidity, temperature) for 15-18 hours. In conventional IVF the sperm fertilizes the egg. For this to happen, the sperm must have the ability to fertilize the egg and the egg must not have a very thick outer membrane. Also, there shouldn’t be any immune system problems since for the sperm to enter the egg, it first has to bind to the egg membrane and any anti-sperm antibodies present can inhibit this binding. IVF can easily be performed as long as there isn’t an important sperm problem. Because of this, if the sperm count, motility or morphology is found to be insufficient after sperm washing, MICROINJECTION (ICSI) should be performed. The first difference be
ICSI (intracytoplasmic sperm injection) is a technique which is used in IVF when there is a male factor issue ( too few sperm, poor sperm motility, high numbers of abnormal sperm) or when there is unexplained infertility. Individual sperm are picked up with a needle under a high powered microscope and injected into an egg. This by passes any problems that the sperm has in physically getting into the egg.
In conventional IVF, a large concentration of sperm are added to a dish containing an egg which has been collected from a woman. The sperm will swim to the egg and fertilise naturally. This mimics what happens in vivo.
Both techniques result in fertilisation but with ICSI, the sperm need a help getting into the egg. You can find out more about ICSI here.
