Intracytoplasmic morphologically selected sperm injection

A technique used in assisted reproductive technology

Intracytoplasmic morphologically selected sperm injection (IMSI) is an advanced assisted reproductive technology (ART) technique used in the treatment of male infertility. It is a variation of the intracytoplasmic sperm injection (ICSI) procedure, which involves the direct injection of a single sperm into an oocyte. IMSI enhances this process by selecting sperm with optimal morphology using high-magnification microscopy.

Procedure

Microinjection of a human egg

The IMSI procedure begins with the collection of a sperm sample from the male partner. The sample is then prepared and analyzed under a high-powered microscope, typically with a magnification of around 6000x, compared to the 400x magnification used in standard ICSI. This allows embryologists to assess the sperm morphology in greater detail, identifying sperm with the best structural characteristics.

Once the optimal sperm are selected, they are used in the ICSI process, where a single sperm is injected directly into the cytoplasm of an oocyte. This precise selection process aims to improve the chances of successful fertilization and subsequent embryo development.

Advantages

IMSI offers several potential advantages over traditional ICSI:

• Improved Selection: By using high-magnification microscopy, IMSI allows for the selection of sperm with superior morphology, potentially leading to better fertilization rates.
• Reduced Risk of Genetic Abnormalities: Selecting sperm with fewer morphological defects may reduce the risk of genetic abnormalities in the resulting embryos.
• Higher Pregnancy Rates: Some studies suggest that IMSI may lead to higher pregnancy rates and lower miscarriage rates compared to conventional ICSI.

Limitations

Despite its advantages, IMSI also has limitations:

• Time-Consuming: The process of selecting sperm under high magnification is more time-consuming than standard ICSI.
• Cost: IMSI is generally more expensive due to the specialized equipment and additional time required.
• Availability: Not all fertility clinics offer IMSI, as it requires specific expertise and technology.

Applications

IMSI is particularly beneficial in cases of severe male infertility, where sperm quality is a significant concern. It is also used in cases of repeated IVF failure or recurrent miscarriage, where sperm quality may be a contributing factor.

Related pages

• Intracytoplasmic sperm injection
• In vitro fertilization
• Male infertility
• Assisted reproductive technology