Intracytoplasmic Morphologically Selected Sperm Injection (IMSI) follows the same principle as ICSI, but with a key difference: sperm selection is performed under an ultra-high-magnification microscope (6,000x to 10,000x). This allows embryologists to closely examine sperm morphology, aiming to choose the most “normal-looking” sperm for injection.
When Is IMSI Recommended?
The benefits of IMSI remain controversial, as studies have not consistently shown higher success rates compared to conventional ICSI. However, it may be considered in cases of:
- Repeated IVF implantation failure (with or without ICSI).
- Severe teratozoospermia (abnormally shaped sperm).
- High sperm DNA fragmentation (which can affect embryo quality).
- Low fertilization rates in previous ICSI cycles (fewer zygotes than expected based on the number of eggs fertilized).
While IMSI offers a more detailed sperm selection process, its real-world benefits remain debated, and it is not routinely recommended for all patients
