Intra Cytoplasmic Morphologically Selected Sperm Injection (IMSI) is a variation of ICSI that uses a higher-powered microscope to select sperm. This allows embryologists to look at the sperm in greater detail (including the nucleus which contains the sperm’s genetic material). Some studies suggest that using this technique selects better quality sperm and results in higher pregnancy rates and lower miscarriage rates compared to conventional ICSI.
The shape of the sperm (morphology) is important in diagnosing male fertility problems and in predicting fertilization and pregnancy outcomes – and studies have shown that selecting better shaped sperm does improve ICSI outcomes.
In conventional ICSI, the embryologist selects the most normal-looking motile sperm using a microscope that magnifies the sample up to 400 times. IMSI is a variation of ICSI that uses a high power light microscope (enhanced by digital imaging) to magnify the sperm sample over 6000 times. This allows the embryologist to detect subtle structural alterations in sperm that a normal microscope could not detect. Sperm are then selected which have the most normally-shaped nuclei. IMSI may improve the chances of fertilisation in vitro and can be used if you have performed several unsuccessful In Vitro Fertilization attempts.
During IMSI, we use a very high power microscope to magnify the sperm around 7000 times. This allows us to see in great detail how the sperm looks and to select the best sperm for the ICSI procedure. IMSI is our latest development for male factor infertility.
If we feel you are going to benefit from IMSI we’ll discuss this with you. Once the best sperm has been selected the IMSI procedure is carried out in exactly the same way as ICSI.