Sperm preparation methods significantly effect
the results of assisted reproduction techniques. Sperm
washing removes cells potentially harmful to fertilization
and obtains more motile and morphologically better
sperm. Conventional sperm washing techniques, include
centrifugal, non-centrifugal swim-up and centrifugal
gradient methods. Sperm DNA fragmentation is one
of the factors suggested for male infertility. Sperm
washing methods may effect DNA fragmentation rate.
The aim of the current study is to compare sperm DNA
fragmentation rates between conventional sperm
washing methods and relatively new microfluidic chip
Methods: Study group consisted of 14 volunteer
men. Every sperm sample was allocated and washed
separately in 3 categories as; gradient, non-centrifugal
swim-up and finally microfluidic chip methods.
Sperm DNA fragmentation rates in each category
were compared by TUNEL (Terminal deoxynucleotidyl
transferase dUTP nick end labeling) test.
Results:Ratio of TUNEL positive sperm with DNA
fragmentation were 12%, 4% and 4,5% by gradient,
non-centrifugal swim-up and microfluidic chip
methods, respectively. Sperm DNA fragmentation ratio
by gradient method statistically significantly increased
compared to those with non-centrifugal swim-up and
microfluidic chip methods (p<0.002). There was no
statistical difference between non-centrifugal swim-up
and microfluidic chip methods (p=0.583).
Conclusion: Current study determined increased
sperm DNA fragmentation rate by gradient method
compared to non-centrifugal swim-up and microfluidic
chip methods. Centrifugation may increase oxidative
stress, and thus lead to free radical production.