Novel Techniques of Sperm Selection for Improving IVF and ICSI Outcomes
Written by Ben Bunting: BA(Hons), PGCert.
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Having an advanced understanding of sperm selection techniques is important for improving outcomes for IVF and ICSI. This article provides information on a variety of different types of sperm tests, including DGC, AV-MACS and the Hypoosmotic Swelling Test. It also discusses how these tests can be used in conjunction with other techniques to optimize outcomes.
AV-MACS
AV-MACS techniques for improving IVF and ICSI outcomes are not new. However, more studies are needed to better understand the role these new methodologies play in pregnancy rates and live birth rates.
The use of HA-ICSI (Hyaluronic Acid Binding ICSI) and IMSI (Motile Sperm Organelle Morphology examination) has been shown to increase the quality of sperm selected for IVF and ICSI. Using these techniques has the potential to improve the reproductive success of couples with severe sperm quality problems.
These methods involve exposing a sperm to a hyaluronic acid sheet in order to select for a higher quality sperm. The resulting sperm have been found to have a lower DNA fragmentation level, which can be beneficial to couples. Early studies also have suggested that HA-ICSI increases fertilization rates and live birth rates.
IMSI is a more thorough examination of sperm, which allows for more detailed analysis of the sperm's structure. The test is relatively inexpensive and easy to perform. The results of this test can be used to isolate a sperm with the lowest DFI level, which may be useful for couples who have persistently high sperm DFI.
The MACS technique is an alternative method for selecting sperm, which uses a Nano-sized mixture of particles with high magnetic properties. These particles are coated with glycoproteins, which helps to reduce the occurrence of abnormal morphological defects.
The MACS method is effective at increasing fertilization rate and blastocyst formation. This is especially helpful for couples with a history of multiple failed IVF cycles. This method has the added advantage of not requiring heavy centrifugation, which can be time-consuming.
A recent study has shown that a HA-ICSI cycle produced a similar live birth rate to Traditional ICSI. However, the HA-ICSI approach is not widely used clinically. It has been suggested that a larger study is needed to further determine if HA-ICSI is effective in reducing sperm DNA fragmentation.
The study used a sample of 228 men with elevated sperm DFI levels. They were given a choice of either ejaculated or testicular sperm. They were then tested for sperm DFI with a fine needle aspiration. This test can be performed after three consecutive ejaculations.
DGC
During IVF and ICSI, there are several techniques to improve outcomes. One of the more common is density gradient centrifugation (DGC). This technique allows for the selection of mature sperm with higher levels of motility. It is also known to reduce sperm DNA fragmentation.
To assess the efficacy of the DGC procedure, a randomized clinical trial was performed. Two hundred and twenty couples with male factor infertility were enrolled. They were randomly allocated to the ICSI group or the DGC group. All clinical and laboratory results were compared between the two groups. A chi-square test was used to detect differences in the two groups.
The number of oocytes retrieved in the DGC and SU groups was comparable. The DGC group had 2418 oocytes while the SU group had 1190 oocytes. The DGC/Zeta group had significantly more expanded blastocysts and good embryo quality.
The DGC technique is easy to perform in sterile conditions. It requires 20 minutes of centrifugation. The pellets are prepared with TALP and Redigrad. Using this method, a large volume of sperm is selected in a single step. The resulting sperm is ready for fertilization.
The DGC and SU techniques for improving IVF and ICSI outcomes are both recommended by the World Health Organization. However, the benefits and risks associated with these two sperm preparation methods are still not well understood. Consequently, further studies are needed to determine whether these methods have a positive or negative effect on reproductive outcomes.
In this study, the main objective was to determine the effects of DCG on sperm morphology and DNA integrity. To do so, fresh semen were subjected to DCG in sperm grade 40% and 80% solutions. The effects of the procedure on sperm DNA integrity were tested using TUNEL/PI. The authors found that 50% of the subjects had increased levels of DNA fragmentation. They concluded that DGC might not be the best method for preparing sperm.
In addition, the results were not very statistically significant. The only statistically significant difference between the two groups was the proportion of conventional IVF cycles. Moreover, the results showed that the SU group had a lower miscarriage rate and higher pregnancy rates.
Hypoosmotic swelling test
HYPO-OSMOTIC SWELLING TEST (HOST) is a method to evaluate the integrity of the plasma membrane of human sperm. Sperm with a functional plasma membrane are less prone to acrosome reaction, apoptotic markers, and abnormal head morphology. The functional membrane plays an important role in sperm captivity, spermatozoon attachment to the oocyte, and in fertilization.
Studies have suggested that the hypoosmotic swelling test is a reliable indicator of sperm quality. It can be used to select viable sperm from nonmotile sperm samples and to improve IVF and ICSI outcomes.
The sperm selection procedure is usually based on morphology and mobility observed under the microscope. The sperm are then analyzed for the presence of chromatin and nuclear DNA. It is commonly used to select sperms for ICSI cycles.
It is known that the sperm with a functional plasma membrane are more likely to be fertilized by the female partner. They also have lower incidences of apoptotic markers and membrane damage.
In order to increase the probability of insemination of sperm with a functional plasma membrane, the HOST test is applied. The technique uses an exposure of a sperm to a hypoosmotic solution for 15 minutes. A microinjection needle is used to remove the sperm. Upon retrieval, the sperm tails are swollen and curled. This swollen tail indicates a functional membrane.
A study has shown that HOST can be applied to increase the rate of live births in infertile couples. Although the results are not statistically significant, it is possible that the test can be beneficial in improving IVF and ICSI outcomes. The researchers compared the pregnancy rates of couples who underwent the HOST procedure to those who did not. They found that the group that underwent HOST had a higher live birth rate and an increased rate of clevage.
In addition to its use as an indication of sperm quality, the HOST has also been used to evaluate the sperm's potential to pass water in a hypoosmotic state. It has been used in the treatment of asthenozoospermia and for assisting in fertility in men with suboptimal semen parameters.
Sperm selection on morphology
Various methods for sperm selection on morphology have been developed to improve IVF and ICSI outcomes. They increase the odds of selecting sperm with structural integrity, mature morphology, and intact chromatin.
These selection techniques are used in clinical fertility management for patients with male infertility. They include intracytoplasmic morphologically selected sperm injection, hyaluronic acid selection, laser beam selection, birefringence, and microfluidics. Several studies have been performed to test the impact of these techniques on sperm quality.
The most common method for ICSI is intracytoplasmic morphologically selected injection (ICMSI). This procedure involves the injecting of one sperm into the oocyte. The process has been improved by the introduction of a micromanipulation system, MSOME. Its integration into ICSI has led to high-magnification micro-injection of spermatozoa. The procedure has also helped embryologists become aware of the importance of a standardized sperm selection procedure for ICSI.
ICSI is a standard treatment for male infertility. However, it has a low success rate. Increasing the chances of successfully fertilizing an oocyte is the goal of the ICSI procedure. The ICSI success rate depends on the patient's age, the oocyte quality, and the selected sperm quality. In addition, the sperm must be healthy and free of toxic substances.
A sperm selection procedure was developed to allow a micromanipulation system to select motile spermatozoa for ICSI. It was based on the interaction between Annexin V and magnetic microspheres. The sperm are then injected into the oocyte through a sharp micropipette.
Several research teams have suggested that the birefringence of the sperm cell head might be a good indicator of sperm suitability. The hypo-osmotic swelling test is another alternative method for sperm selection. It is based on the assumption that the tails of viable sperm swell in a hypoosmotic environment.
Another method for sperm selection is polarized light. This technique is used to separate apoptotic sperm from non-apoptotic sperm. In a study, a spermatozoon with no vacuoles was found to be a better option than a spermatozoon with vacuoles.
In the current era of clinical infertility, a sperm selection system must be fast and simple. It should also be cheap.
Conclusion
Various methods of sperm selection have been developed to achieve better quality sperm for IVF and ICSI. These methods include density gradient centrifugation, annexin V-conjugated microbeads, electrophoresis, swim-up assay, and hyaluronic acid bonding. However, most of these techniques involve removing a large portion of the sperm. Despite this, many authors report a higher implantation rate, improved embryo production, and decreased miscarriage rates.
In this study, a novel distance-progesterone-combination selection approach was investigated. It was based on the characteristics of the human female reproductive tract, including sperm chemotaxis, and was evaluated on a small pool of couples undergoing ICSI. The goal of the study was to evaluate the efficiency of the method and its effect on apoptosis and DNA fragmentation.
The results showed that the percentage of sperm with DNA fragments at position E2 did not differ significantly from that at position D2 after selection. A lower percentage of sperm with DNA fragments was found in sperm that were treated with Percoll before selection.
The results of the study suggest that the SU technique is more effective than the DGC. Furthermore, sperm selected by the SU method have a higher percentage of extranuclear DNA fragments than sperm that were selected by the DGC.
Another advantage of this method is the ability to select sperm cells with a high level of motility. It is a safe and economical method. The horizontal swim-up process allows for recovery of spermatozoa with minimal DNA damage.
