ICSI stands for Intracytoplasmic Sperm Injection.

The first pregnancy achieved through ICSI dates back to 1992. Nowadays, it is a routine technique widely used in embryology laboratories.

ICSI, which acts directly on the first stage of fertilisation, is a variant of in vitro fertilisation (IVF) with a different insemination technique. In this case, a single sperm is injected directly into each egg using specialised microscopic and micromanipulation equipment.

The observation, selection, and microinjection of sperm are carried out under an inverted microscope at 400x magnification. These sperm are usually obtained from the ejaculate, but in specific cases, such as azoospermia, they can be retrieved through a testicular biopsy.

ICSI is particularly recommended in cases of severe male factor infertility, repeated fertilisation failures in IVF treatments, and recurrent miscarriage. However, due to its effectiveness and safety, ICSI is now used in most IVF cycles.