Evaluation of sperm DNA fragmentation after cryopreservation in ejaculated spermatozoa

Introduction: Infertility has been declared as a public health concern by the World Health Organization. Infertility affects approximately 10%-15% of couples worldwide. Male factors contribute significantly to infertility approximately 35% of couples. Assessment of the integrity of sperm DNA is important in male infertility. Semen cryopreservation techniques as a measure of fertility preservation have been shown to increase DNA fragmentation. The main objective is to study the effects of cryopreservation on sperm DNA fragmentation in ejaculated spermatozoa. Material and Methods: The study was conducted in a tertiary care referral hospital for infertility during the period of January 01, 2013-March 31, 2014. A total of one hundred patients who met the inclusion criteria were included in the study. Sperm DNA fragmentation was done prefreeze and postthaw by sperm chromatin dispersion test. Results: Mean sperm count prefreeze was 56.6 million/ml (standard deviation [SD] = 22.5 million) of semen. Lowest concentration of spermatozoa in the study population was 25 million/ml of semen and highest concentration of spermatozoa in the study population was 120 million/ml of semen. Postfreeze concentration had mean of 66.1 million (SD = 22.4 million). DNA fragmentation in prefreeze was 3.5% (0.3%) and in postfreeze 3.6% (0.3%). There was statistically significant difference between prefreeze and postfreeze values both in sperm count and DNA fragmentation. There was a statistically significant correlation between age and postthaw DNA fragmentation. Discussion and Conclusion: Although cryopreservation increases the DNA fragmentation level of washed sperm significantly, this does not prevent us from utilization of cryopreservation facility because benefits far outweigh the adverse effects of cryopreservation.