Intraindividual variations of the sperm DNA fragmentation index

Abstract

Background

The aim of this study was to analyse and compare both, inter and intra individual baseline Sperm DNA fragmentation (SDF) fluctuations in two different groups of men: 1) those attending an infertility clinic for the purpose of seminal analysis and 2) those fertile individuals that donate semen for assisted reproduction techniques.

Material and Methods

Semen samples from 51 patients (Patient Sample-PS) (n=145) attending an infertility clinic and from 18 healthy donors (Donor Sample-DS) (n=128) providing semen for an artificial insemination program were included in this analysis. Between 4 and 6 SDF measurements per subject were performed. SDF fragmentation was assessed using the Halosperm kit (Halotech DNA, Madrid, Spain). To estimate the interindividual variability, the standard deviation of the mean of the values of the first seminal sample of the 69 individuals included in the study was calculated. For the computation of the intra-individual variation, the mean of the dispersion of each subject was calculated by means of the standard deviation with respect to the mean of the set of all their examined samples of those individuals who had at least four samples analysed. The coefficient of variation (CV) for sperm DNA Fragmentation (SDF) was calculated using the formula (SD/mean) x100.

Results

The analysis of the first sample resulted in a distribution with a mean of 31.74 and an SD of 14.14, with an intra-individual variability (calculated by CV) of 0.45 or 45%.

The mean of the 4.8 samples analyzed for everyone showed a mean IF of 30.49% with an SD of 8.76% and an intra-individual variability (CV) of 0.33 or 33%.

Conclusion

When establishing cut-off points applicable to daily clinical practice, it is necessary to consider the importance of the high intraindividual variability in DNA fragmentation of different samples of your semen.