Intracytoplasmic sperm injection is performed as part of in vitro fertilization (IVF) to inject sperm into the egg to help it fertilize it. This assisted reproductive technique has been the most successful treatment for male infertility and is used in nearly half of all IVF cases.

Normally, the egg is fertilized when the sperm moves into the egg, however, in cases where the sperm cannot penetrate the egg due to the thick outer layer of the egg or the sperm is weak, leading to male infertility. In this case, the doctor will perform the technique of injecting sperm into the egg cytoplasm to help the sperm complete the fertilization process.