Intracytoplasmic sperm injection (ICSI) involves the direct injection of sperm into the eggs obtained by the process of (IVF) in vitro fertilization. This treatment is a specialized form of IVF that is used for the treatment of severe cases of male-factor infertility. ICSI treatment involves the injection of a single sperm directly into a mature egg. 

In ICSI the mature egg is held with a specialized pipette. A hollow needle is used to immobilize and pick up a single sperm which is then injected into the cytoplasm of the egg. The eggs are checked the following day for evidence of normal fertilization. Once the fertilization is successful, the embryos are cultured in the lab. After the embryos are ready, they are placed in the woman’s uterus. 

ICSI is recommended if there is any difficulty in achieving fertilization due to male factors like 

1) Low sperm count

2) Poor sperm motility

3) Decreased ability of sperm to penetrate into the egg 

4) poor sperm quality 

5) Previous unsuccessful IVF procedure  

6) previous failure of fertilization 

ICSI is also recommended in patients with Azoospermia. Azoospermia is a condition where there is no sperm in the male’s ejaculate. There are two types of azoospermia: obstructive and non-obstructive. Obstructive azoospermia may be caused by any of the following:

• Previous vasectomy 

• Congenital absence of the vas

• Scarring from prior infections

Non-obstructive azoospermia occurs when the testicles are not producing sperm. 

In cases with azoospermia, sperm can be obtained directly from the testicles by various techniques and this sperm can be used to fertilize the egg by the process of ICSI.