IMSI IVF Treatment: Selecting the best sperm for fertilisation
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IMSI treatment

Intracytoplasmic morphologically selected sperm injection (IMSI) is an additional technique we may use when ICSI is included as part of the IVF process, to help select the best sperm for injection and further improve the chances of fertilisation.

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When is IMSI necessary?

IMSI is an additional procedure we may use to aid the success of an IVF treatment cycle if semen analysis suggests abnormal sperm morphology (i.e. shape). If a sperm is abnormally shaped, it may have trouble fertilising the female egg. If the results of your semen analysis suggests that issues with shape are acting as a barrier to successful pregnancy, we may recommend IMSI to aid selection of the best sperm for IVF, i.e. those that are normal looking in appearance.

IMSI is not suitable for all sperm-related issues associated with male factor infertility. Based on your personal semen analysis results, your fertility specialist will inform you if IMSI is recommended to aid the success of your next IVF treatment cycle. Typically, IMSI will be recommended if you have had poor results with the use of ICSI alone, i.e. lower than expected fertilisation rates with ICSI.

How does IMSI work?

IMSI involves the use of an extremely high-powered microscope (one that can magnify structures over 6000 times!) to visualise a sperm’s head, midpiece and tail. This enables our scientists to better identify any structural abnormalities that may prevent the sperm from successfully fertilising an egg. This knowledge then allows us to select the optimal sperm for injection via ICSI, thereby improving the likelihood of successful fertilisation.

What are the success rates with IMSI?

Like ICSI, the use of IMSI during IVF treatment can help overcome some very specific sperm-related issues associated with male factor infertility. However, it’s important to note that the success rate of IMSI also depends on other factors that can impact the chances of fertilisation occurring, such as age and egg quality.

Do all IVF providers offer IMSI?

The injection of a single sperm into an egg requires expert technique and precision. Thus, this procedure can only be performed by a suitably experienced embryologist. At Newlife IVF, all IMSI and ICSI procedures are performed by Senior Embryologists in our state-of-the-art IVF laboratory at our fertility treatment centre in Box Hill.

Frequently asked questions

  • How does IMSI work?

    Your fertility specialist may recommend IMSI if your semen analysis results indicate abnormal sperm morphology (i.e. abnormally shaped). If ICSI is being used as part of an IVF treatment cycle, IMSI is an additional technique that may be used to aid the selection of the best-looking sperm for injection into a mature egg via ICSI. At the time of ICSI, our embryologists examine the sperm under a very high-powered microscope (x6000). This allows them to assess sperm morphology (i.e. the shape of sperm), including the head, midpiece and tail. By doing so, our embryologists can identify sperm that are less likely to fertilise an egg (i.e. sperm with abnormalities), as well as healthy sperm that have a greater chance of successful fertilisation. This enables our embryologists to choose the best-quality sperm to use during ICSI.

  • When do we use IMSI?

    Our fertility specialists may recommend IMSI if your semen analysis suggests that the sperm are abnormally shaped, which can reduce the chances of conception. For instance, sperm with irregular tails may have difficulty reaching the egg, while sperm with abnormally shaped heads have difficulty penetrating the egg’s outer layer.

     

  • How does IMSI treatment differ from conventional IVF?

    In IVF with ICSI, sperm are selected based on their motility (movement) and morphology (shape) under a standard microscope. However, IMSI uses a high-powered microscope to magnify sperm cells by up to 6,000 times, allowing for a more detailed examination of sperm morphology so that the healthiest-looking sperm is selected for injection into the egg.

  • What are the advantages of IMSI treatment?

    IMSI treatment provides a greater ability to select sperm with the best morphology, therefore minimising the risk of injecting abnormal or damaged sperm into the egg. This may improve fertilisation rates, embryo quality and, ultimately, the chances of successful pregnancy and live birth.

  • Are there any risks or side effects associated with IMSI treatment?

    IMSI treatment is generally considered safe, and the risk of complications is low.

  • Is IMSI treatment suitable for everyone undergoing IVF?

    IMSI treatment may not be necessary or suitable for all couples undergoing IVF. It is typically recommended for couples with specific male factor infertility issues or previous IVF failures. It is essential to consult a fertility specialist to determine whether IMSI treatment is appropriate based on individual circumstances.

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Get in touch

For more information or to book an appointment with one of our fertility doctors, please call (03) 8080 8933 or email [email protected]. Fertility appointments can also be booked via our online booking page.

Our three Melbourne clinics are based in Box Hill, Clayton and East Melbourne and are open Monday–Friday: 8:00am–5:00pm. We welcome patients from all over Victoria, as well as those seeking care interstate or internationally. All fertility treatment requiring day surgery or lab access (e.g. egg collection, embryo transfer) will take place at our state-of-the-art treatment centre in Box Hill. Fertility consultations and IVF cycle monitoring can be arranged at all three Melbourne clinics.

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