Effect Of Abstinence Days,storage Time After Semen Optimization And Temperature On Sperm DNA Fragments

Background and ObjectivesIn recent years,the number of couples suffering from fertility problems has increased year by year.Infertility has become a medical problem and a social problem that is widely concerned in the world.The male factor in infertility cases accounts for 50%of the total cases.With the development of technology,assisted reproductive technology(ART)has helped many infertile couples solve their fertility problems.Embryo quality is an important factor that affects the success rate of ART,and sperm DNA,as a provider of half of the genetic material of the fertilized egg cell nucleus,is essential for embryo formation and development.The integrity of sperm DNA will affect sperm fertilization ability,embryonic development potential,fetal growth and development,and offspring health.In the case of mild DNA damage,the fertilized oocyte can start a limited DNA repair program to repair,but under the interference of harmful factors,sperm DNA fragments are produced in large quantities,which exceeds the repair capacity of the oocyte and may activate the apoptosis pathway to induce embryogenesis.Sperm DNA fragmentation index(DFI)can measure the degree of sperm DNA damage,has good stability,and can effectively reflect the integrity of sperm DNA.Studies at home and abroad have shown that sperm DFI has a strong correlation with the decline of females’ natural pregnancy rate and male infertility.The DFI of infertile men is significantly higher than that of fertile men.25-40%of infertile men have regular semen characteristics.Normal,but DFI is as high as 20-30%,exceeding the normal threshold,male fertility declines.Therefore,many domestic reproductive centers have used DFI as an important indicator to evaluate the quality of semen.Obtaining high-quality sperm for fertilization is a prerequisite for the formation of high-quality embryos.The time of abstinence is crucial to ensure the number and quality of sperm required for successful natural and assisted pregnancy.However,the reports on the effects of different days of abstinence on sperm DNA fragments are not consistent.The effect of abstinence days range on sperm DFI is not yet fully studied,and this article intends to further study this.If the number of days of abstinence affects the sperm DFI level,semen samples with less debris can be obtained by interfering with the time of abstinence as much as possible to assist in the process of assisted reproduction and improve the success rate of assisted reproductive technology.Previous studies have confirmed that temperature and storage time will adversely affect the sperm DNA fragmentation rate.In the process of assisted reproduction,semen needs to be subjected to in vitro optimization treatment for fertilization.The impact of the in vitro operation process on the fertilization ability of sperm cannot be ignored.In order to understand the effect of temperature and storage time on sperm DNA fragments,this article intends to explore the changes in sperm DNA fragments after optimizing sperm’s built-in sperm at 0-6h at room temperature(24 ± 1 ℃)and 37℃,and explore the best conditions for sperm placement And time to reduce the generation of sperm DNA fragments,thereby improving IVF-ET pregnancy outcomes.Materials and MethodsThe clinical data of 824 male patients who were treated at the Reproductive Medicine Center of the Second Affiliated Hospital of Zhengzhou University from February 2019 to July 2019 were selected and divided into G1(<2d),G2(3-5d),G3(6-7d),G4(>7d)4 groups,compare the DFI,forward movement,concentration and other indicators of each group.Thirty normal semen specimens from male patients who were treated at the same time were randomly selected.They were collected by masturbation after 2-7 days of abstinence,and the DFI value of the semen samples was determined.After sperm optimization treatment,the sperm DFI value was measured again,and then divided into two,placed in room temperature(24 ± 1 ℃)and 37 ℃ incubator,the DFI value was detected at 2h,4h,6h,Group A:before semen optimization DFI value;Group BO/CO:DFI value measured immediately after semen optimization treatment;Group B2:DFI value at room temperature 2h;Group B4:DFI value at room temperature 4h;Group B6:DFI value at room temperature 6h;Group C2:DFI value at 37 ℃ for 2h;Group C4:DFI value at 37 ℃ for 4h;Group C6:DFI value at 37 ℃ for 6h;compare the changes in DFI of related groups,and explore the effect of placement time and temperature on sperm DFI.Results1.Variation of semen analysis parameters for different abstinence days:The change rule of semen DFI for different abstinence days is:G4 group(abstinence>7 days)>G3 group(abstinence 6-7 days)>G2 group(abstinence 3-5 days)>G1 group(abstinence>2 days),G4 group and G3 group were significantly higher than G1 group and G2 group,the difference was statistically significant,P<0.05;the proportion of sperm forward movement on different abstinence days was:G2 group>G4 group>G3 group>G1 group,there is no statistically significant difference between groups,P>0.05;sperm concentration in different abstinence days is as follows:G4 group>G3 group>G2 group>G1 group,G4 group is significantly higher than G1 group,The difference was statistically significant,P<0.05.2.After density gradient centrifugation and upstream treatment,the sperm DFI was significantly reduced,the difference was statistically significant,P<0.05.3.The change of sperm DFI at different temperatures and different times after sperm optimization:6h group>4h group>2h group>Oh group(ie B6 group>B4 group>B2 group>B0 group)at room temperature,The B6 group was significantly higher than the B0 group,the difference was statistically significant,P<0.05.At 37℃ placed 6h group>placed 4h group>placed 2h group>placed 0h group(ie C6 group>C4 group>C2 group>C0 group),The differences between the groups were statistically significant,P<0.05.4.The effect of different temperatures on sperm DFI:DFI in the 37℃ incubator at the same time after the same optimized sperm is greater than room temperature,ie C2 group>B2 group,C4 group>B4 group,C6 group>B6 group,P<0.05.Conclusions1.The best sperm quality in 3-5 days of abstinence;2.After sperm optimization treatment,the sperm should be placed in vitro for less than 2h before in vitro fertilization.When remedying ICSI,try to do it within 6h after sperm optimization treatment;3.After optimized semen treatment,it is better to put it at room temperature before fertilization than 37℃ incubator.