Intracytoplasmic Morphologically-Selected Sperm Injection (IMSI) is a technique used in assisted reproduction, specifically In vitro fertilization (IVF) procedures. It is a form of intracytoplasmic sperm injection (ICSI) in which the sperm is examined at high magnification before being injected into the egg. The goal of IMSI is to improve the chances of fertilization and pregnancy by selecting sperm that have the best morphology (shape and structure) for injection. This technique is typically used in cases where there is a high degree of sperm abnormality or where previous IVF attempts have failed.