Introduction: About half of the causes of infertility are related to men. The sperm of infertile men often have different functional and structural defects. Among these defects is sperm DNA damage, which can be caused by DNA fragmentation, improper chromatin packaging, and epigenetic defects. All men have some degree of damage to sperm DNA, but when the percentage of this damage increases significantly, it causes pregnancy disruption, miscarriage, and failure in assisted reproductive methods. Studies have shown that 15% of couples are unable to have children despite trying to conceive and are considered infertile, with half of these cases of infertility being due to male factors. The majority of male infertility is due to abnormal sperm. Therefore, these individuals are candidates for assisted reproductive techniques such as IVF and ICSI and may have tried these treatments repeatedly and failed. One of the most important factors in the success of in vitro fertilization is the health of sperm DNA. Various studies show that the lower the quality of sperm, the more problems sperm DNA health faces.

Aims: Therefore, the purpose of conducting research to identify sperm DNA damage and study its effect on the success rate of assisted reproductive methods, including microinjection, in infertile couples is essential, with the aim of improving sperm quality before starting the treatment cycle and imposing excessive costs on couples.



Materials and methods: The present study was experimental and appropriate laboratory equipment, materials, and solutions were used in the research process. In this experiment, semen samples were collected from 60 infertile couples (30 of which were considered positive control samples) who had referred to the Royesh Infertility Treatment Center in Karaj for ICSI treatment. Oligoasthenospermia samples and positive control samples were selected and separated. Anti-Mullerian hormone (AMH) of women candidates for ICSI, which is present in the patient's serum and measured through a blood test, was examined, and those with AMH equal to 2 and above were selected. Then, sperm washing was performed for intracytoplasmic injection. Sperm injection into the egg is usually done 2-3 hours after ovulation. In the next step, sperm DNA breakage was assessed. Failure assessment was performed immediately after sample receipt. The collected data was analyzed using SPSS software, which provides a summary of the methods and techniques used.

Results: The average embryo quality in the normal sperm group was 93.35%, while this index was only as high as 75.74% in the DNA-damaged sperm group. Also, the average sperm velocity in the normal sperm group was 36.2%, while this index in the DNA-damaged sperm group showed a small value of 5.53%. Also, The average percentage of non-motile sperm, sperm with DNA breakage was 82.17%, and in the normal sperm group, the average was 41.93%. In addition, in the DNA breakage sperm group, the average percentage of sperm with rotational movement was 17%, sperm with slow progressive movement was 5.4%, and sperm with fast progressive movement was 0.1%, while in the normal sperm group, the desired indicators showed averages of 0.87%, 25.13%, and 11.07%, respectively. The results of the study also showed that sperm with DNA breakage has a significant impact on reducing embryo quality. And sperm DNA damage can severely and significantly reduce sperm velocity and count. And finally, sperm DNA breakage has a significant impact on sperm shape.

Discussion: The results obtained indicate that DNA breakage is more common in oligoasthenospermic individuals than in healthy individuals, and this breakage significantly affects embryo quality.

Conclusion: Since in assisted reproductive methods, damage to sperm DNA may cause treatment failure, it is recommended to check the sperm DNA fragmentation rate (SDFA) before choosing the appropriate treatment method. And in many cases, if there is damage to sperm DNA, appropriate treatment can improve sperm quality. SDFA testing is a reliable method for assessing sperm DNA health, which greatly contributes to the clinical diagnosis and treatment of male infertility and is of great value in the success of treatment methods.