Comparison of the DNA Fragmentation and the Sperm Parameters after Processing by the Density Gradient and the Swim up Methods

Abstract

Introduction:The swim up and the density-gradient centrifugation are the two main techniques which are used to separate the viable motile sperm fraction in the assisted reproductive technology. However, there are several published studies about these methods, but there is no sufficient evidence for recommending the superiority of one of them. This study was designed to study the efficiency of the swim-up and the density gradient techniques to recover the spermatozoa with a high degree of motility, a normal morphology and a low level of DNA fragmentation. Material and Methods:A total of 35 semen samples were included in the study. The semen samples were collected, one part of the semen was spread on a slide and the remainder was prepared by using the swim-up or the density gradient techniques. The recovered spermatozoa were evaluated for concentration, motility, and normal morphology. A comet assay was carried out to assay the DNA fragmentation in all the samples.Results: There were significant differences in the sperm parameters between the density gradient and the swim up techniques. Also, the swim-up technique showed a significantly higher level of DNA fragmentation as compare to the density gradient technique. Conclusion:The results of this study demonstrated several benefits of the gradients method in the separation of normal and motile spermatozoa with healthy DNA, in comparison to the swim up method.

The pellet swim-up is the best technique for sperm preparation during in vitro fertilization procedures

“…However, our results are inconsistent with the findings presented by Amiri and colleagues [26], which compared the swim-up and density gradient preparations on samples of men undergoing semen analysis. In their study, they found that the DNA-fragmented spermatozoa in the samples prepared with the swim-up method were more numerous than in those processed with the density gradient.…”

“…Moreover, given that three out of four techniques chosen included swim-up procedures, we excluded sperm samples with total motility of less than 35 %. Out of a total of 490 tests undertaken, we observed that all the sperm preparation techniques were able to decrease the total sperm population with DNA fragmentation, in accordance with the findings of other authors [26]. Specifically, only two methods out of the four used-the pellet swim-up and the density gradient followed by swim-up-exhibited the best results.…”

Semen preparation methods and sperm telomere length: density gradient centrifugation versus the swim up procedure

“…Additionally, Ghaleno and colleagues, who obtained semen samples from 28 normozoospermic men, also found that the ROS level was not significantly different between the two methods, but the mean DFI was higher with the DGC method33. However, Amiri and colleagues obtained contradicting results from a study with 35 subjects, in which they found that the number of DNA-fragmented spermatozoa in samples prepared by the SU method was higher than in sperm processed with DGC32. Future more, one study campared the DNA fragmentation of sperm obtained by the DGC, SU and SU following DGC.…”

“…One study that compared the effects of DNA fragmentation of sperm recovered by DGC and SU procedures, either alone or in combination, found no difference between the techniques31. Amiri and colleagues found that the number of DNA-fragmented spermatozoa in samples prepared by the SU method was larger than those in samples processed with the DGC approach32. However, some studies have found that the mean DNA fragmentation in samples processed by DGC was higher than in samples collected with the SU method3334.…”

Sperm Preparation Methods for IUI and IVF

“…Normal morfolojiye sahip ve ileri hızlı hareketli sperm hücreleri-nin, sitoplazma içerikleri daha az olduğundan (daha olgun), oluşturulan farklı yoğunluktaki katmanlardan geçerek konik tüpün dip kısmına ulaşması bek-lenir. 12 En kaliteli spermleri elde edebilmek için konik tüpün en alt katmanı en yoğun katman olarak belirlenmelidir. Buna göre sıklıkla tercih edilen yoğunluk kombinasyonları literatürde yüksek fertilizasyon ve gebelik oranlarıyla karakterize olan 40/80 veya 50/90'dır.…”