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Intracytoplasmic morphologic sperm injection (IMSI)
For most patients, having a routine cycle of proven fertility treatment is effective without using any treatment add-ons.
Our ratings indicate whether the evidence from studies shows that a treatment add-on is effective at improving treatment outcomes for someone undergoing fertility treatment. Our ratings do not tell you how much that treatment add-on improves your chances of having a baby – please discuss this with your clinic.
What is IMSI?
Intracytoplasmic morphologically selected sperm injection (IMSI) is a sperm selection method used in intracytoplasmic sperm injection (ICSI). The technique involves using a microscope to view detailed images of the sperm under very high magnification (over x6000) to select the sperm to inject into an egg.
| Rated outcomes for IMSI | |
|---|---|
| Rated grey for increasing the chances of having a baby for most fertility patients
Grey traffic light
|
We cannot rate the effectiveness of this add-on at for improving the chances of having a baby for most fertility patients as there is insufficient moderate/high quality evidence. |
| Rated grey for patients undergoing treatment due to male factor infertility
Grey traffic light
|
We cannot rate the effectiveness of this add-on at for improving the chances of having a baby for patients undergoing treatment due to male-factor infertility as there is insufficient moderate/high quality evidence. |
What do the ratings mean?
There are five ratings that indicate whether a treatment add-on is effective at improving treatment outcomes for someone undergoing fertility treatment, according to the evidence from studies. To make it easier to understand the scientific evidence for each treatment add-on we have a range of symbols and colours for each rated add-on below.
Green traffic light
On balance, findings from high quality evidence shows this add-on is effective at improving the treatment outcome.
Yellow traffic light
On balance, it is not clear whether this add-on is effective at improving the treatment outcome. This is because there is conflicting moderate/high quality evidence – in some studies the add-on has been found to be effective, but in other studies it has not.
Grey traffic light
We cannot rate the effectiveness of this add-on at improving the treatment outcome as there is insufficient moderate/high quality evidence.
Black traffic light
On balance, the findings from moderate/high quality evidence shows that this add-on has no effect on the treatment outcome.
Red traffic light
There are potential safety concerns and/or, on balance, findings from moderate/high quality evidence shows that this add-on may reduce treatment effectiveness.
All treatment add-ons on our list will have a rating to indicate whether the evidence shows that the treatment add-on is effective at improving the chances of having a baby for most fertility patients. Some treatment add-ons on our list may also have additional ratings for specific treatment outcomes. For example, whether the evidence shows that the treatment add-on reduces miscarriage. There may also be further ratings for specific patient groups, for example whether the evidence shows that the treatment add-on is effective for those who are aged over 40. Please see the individual webpages for each treatment add-on for their ratings.
An agreement between the HFEA and other professional and patient bodies (the 19th October 2023 consensus statement) stated that treatments that have no strong evidence of their safety and/or effectiveness should only be offered in a research setting. Patients should not be charged extra to take part in research, including clinical trials.
What’s the evidence for IMSI?
There have been several randomised controlled trials (RCTs) within the last decade showing very little evidence of benefit of using IMSI, and the evidence is also of low quality. The research that has been carried out does not support the use of IMSI over standard ICSI. One small study found that IMSI had improved pregnancy outcomes in older patients, however this study was carried out with a small number of participants and the link, if any, between IMSI and older eggs is not fully understood.
At the July 2023 Scientific and Clinical Advances Advisory Committee (SCAAC) meeting the Committee evaluated the evidence base for IMSI. Minutes of this discussion and the evidence used to inform this discussion are available on the SCAAC webpage.
This Cochrane review has further information on the evidence for IMSI.
Is this treatment add-on safe?
IMSI is a non-invasive test performed on a semen sample as an additional step in the ICSI process. The risks associated with the use of ICSI also apply to IMSI. However, IMSI does not carry any additional known risks for the person undergoing fertility treatment or the child born as a result of fertility treatment.
If you have any questions about the safety and risks, your clinic will be able to discuss whether a treatment add-on would be safe for you to use considering your specific medical history and circumstances.
Studies reviewed for this treatment add-on
The SCAAC have reviewed the following studies for IMSI:
| Balaban 2011 | 10.1016/j.rbmo.2010.11.003 |
| Figueira 2011 | 10.1016/j.fertnstert.2010.11.018 |
| Setti 2012 | 10.1016/j.rbmo.2012.01.007 |
| Setti 2013 | 10.1016/j.ejogrb.2013.09.006 |
| Marci 2013 | 10.1186/1742-4755-10-16 |
| Cassuto 2014 | 10.1016/j.rbmo.2013.08.013 |
| Setti 2014 | 10.1016/j.ejogrb.2014.10.008 |
| Antinori 2008 | 10.1016/s1472-6483(10)60150-2 |
| Knez 2011 | 10.1186/1477-7827-9-123 |
| Setti 2011 | 10.1016/j.fertnstert.2011.03.003 |
| Knez 2012 | 10.1016/j.rbmo.2012.03.011 |
| Check 2013 | Clin Exp Obstet Gyn 2013;40(1):15-7. |
| De Vos 2013 | 10.1093/humrep/des435 |
| Leandri 2013 | 10.1111/j.2047-2927.2013.00104.x |
| Kim 2014 | 10.5653/cerm.2014.41.1.9 |
| Sifer 2014 | 10.1016/j.ejogrb.2014.07.017 |
| La Sala 2015 | 10.1186/s12958-015-0096-y |
| Mangoli 2019 | 10.1111/and.13340 |
| Mangoli 2020 | 10.1007/s10815-020-01910-7 |
What are treatment add-ons?
In vitro fertilisation (IVF) and intrauterine insemination (IUI) are established treatments that have been proven effective for most patients. Treatment add-ons are optional non-essential treatments that may be offered in addition to such proven fertility treatment. The HFEA provides information on add-ons that meet the following criteria:
- Additional treatments (to the core treatment e.g. IVF or IUI), that are being offered to the general patient population in licensed fertility clinics in the UK,
- Where there are published scientific studies which claim to demonstrate that the treatment add-on improves the chances of having a baby or other treatment outcomes rated by the HFEA; but
- where evidence of effectiveness for the use of the treatment in a clinical setting is lacking or absent; and
- where patients need unbiased information about the effectiveness and risks of this treatment.
It is important to keep in mind that for most patients, having a routine cycle of proven fertility treatment is effective without using any treatment add-ons. If you are paying directly for your own treatment, you may want to think about whether it might be more effective and/or affordable to pay for multiple routine proven treatment cycles, rather than spending large sums of money on a single treatment cycle with treatment add-ons that haven’t been proven to be effective at increasing the likelihood of you having a baby.
We aim to publish clear and reliable information about some of the treatment add-ons that don’t have enough evidence to show that they are effective at improving your chances of having a baby and other relevant treatment outcomes. This provides useful information to patients and allows them to question the use of add-ons
Review date: 19 October 2025
