For many couples, conventional IVF is unlikely to result in fertilisation – either because the number of sperm is too low or because the sperm cannot penetrate the egg. In such cases, we usually carry out Intracytoplasmic Sperm Injection (ICSI treatment). ICSI is also used where the male partner has previously had a vasectomy.
How ICSI works
ICSI treatment involves injecting a single sperm into each egg, using very fine micromanipulation equipment. As the human egg is one tenth of a millimetre in diameter and the sperm 100 times smaller, this is a very delicate procedure performed by highly skilled embryologists using a very sophisticated microscope. We can also use this technique when sperm are not present in the semen, and have to be obtained surgically from the male reproductive tract.
If ICSI is the appropriate treatment for you, your fertility specialist will discuss the procedure with you. If you decide to go ahead, ICSI will be part of your IVF treatment cycle, which you will undergo from start to finish.
ICSI is commonly used when the concentration (sperm count) or motility (movement) is low, or where a very high percentage of the sperm look abnormal on formal testing.
ICSI has not been shown to increase fertilisation rates in situations where the sperm assessment is normal.
Normal fertilisation rates with IVF or ICSI are approximately 50-60%. That is, for every 10 eggs extracted and combined with the sperm, approximately 5-6 will fertilise normally.
