ICSI

What is ICSI (Microinjection)? – Comprehensive Guide

What is ICSI?

ICSI (Intracytoplasmic Sperm Injection) is the process of directly injecting a single sperm into an egg under a microscope. It is an advanced fertilization method used in in vitro fertilization (IVF) treatment.

How Is It Performed?

A mature egg (MII) is immobilized under a microscope, and a single sperm is directly injected into the egg using a special pipette.

When Is It Preferred?

• Low sperm count
• Low motility
• Morphology defects
• Previous IVF failure
• Sperm obtained via TESE
• Unexplained infertility

Difference from Conventional IVF

In conventional IVF, sperm and egg are left in the same medium, whereas in ICSI, fertilization is actively facilitated.

Success Rate

The fertilization rate is generally around 60–80%. However, pregnancy success depends on embryo quality and patient factors.

Advantages

• Increases fertilization chances
• Most effective method for male factor infertility
• Can be applied even with low sperm count

Disadvantages

• Laboratory-dependent
• May incur additional costs
• Does not always guarantee pregnancy

Risks

Generally safe. Very rarely, egg damage or fertilization failure may occur.

Embryo Development

Fertilized eggs are monitored and transferred or frozen on day 3 or 5.

Conclusion

ICSI is a revolutionary method, especially for male factor infertility, and is one of the most commonly used IVF techniques today.