ICSI / IMSI Treatments


What is ICSI?

ICSI is an acronym for Intracytoplasmic Sperm injection. This technique is used to aid fertilisation of eggs in vitro. With ICSI, a single sperm is selected and injected directly into an egg, bypassing the natural fertilisation process. All the other laboratory aspects of the ICSI cycle are the same as an IVF cycle.

Why ICSI can help

Achieving successful fertilisation of mature eggs in vitro is central to the IVF process. In some cases the sperm has to be injected directly inside the egg. ICSI is used when a problem or potential problem with the sperm has been identified during the phase of investigations.

Cases where ICSI may be recommended

  • Abnormal sperm parameters (low sperm count, low sperm morphology and/or motility)
  • Previous history of failed fertilisation with conventional IVF
  • Previous history of abnormal fertilisation as it occurs in cases of gestational trophoblastic disease
  • The sperm has been surgically retrieved


What is IMSI?

Intracytoplasmic Morphologically Selected Sperm Injection (IMSI) is a non-invasive sperm selection process used during the ICSI procedure. IMSI uses a high powered lens to look at sperm under very high magnification and allows the embryologists to see greater detail during the sperm selection process.

Why IMSI can help

Achieving a healthy pregnancy is hugely dependent on the quality of the human embryo. The quality of an embryo is a product of the quality of both the egg and the sperm. If sperm have abnormalities they can still create an embryos but these are unlikely to implant or may result in an early miscarriage.

Some sperm abnormalities can be identified using a microscope which magnifies up to x400. With IMSI the magnification is up to x6000, which enables the embryologists to see more accurately abnormalities in the head of the sperm. By selecting sperm without abnormalities, the chance of creating better quality embryos is higher.

There have been several studies within the last decade that suggest that IMSI could be beneficial in specific situations such as previously failed ICSI attempts. However the research suggests that IMSI only helps certain groups of patients and should not replace standard ICSI. For more information, please see the HFEA website or speak to a member of staff.

Cases where IMSI may be recommended

  • A high number of abnormal sperm are found in a semen analysis
  • Repeated unsuccessful ICSI cycles
  • History of recurrent miscarriages
  • Poor quality embryos formed in previous cycles

Get in touch

If you have a question about any of our services, please call us on 01925 202180 or contact us below.

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If you would like to find out more about ICSI or IMSI Treatment or feel that you can benefit fromICSI or IMSI in your fertility journey then feel free to request an online appointment today. Alternatively, you can call us on 01925 202180, and we will be more than happy to assist you with any other advice.

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