Effects of antioxidants on motility and DNA integrity in frozen-thawed sperm

Abstract

Aims: This study aims to investigate whether the addition of the antioxidant complex including taurine, ascorbic acid, and glutathione into the cryopreservation medium affects the damage to sperm during the freezing process. Methods: Ejaculate samples of patients who applied for semen analysis to the Assisted Reproduction Unit of Private Adatip Hospital were used. Fresh samples were analyzed for standard semen quality parameters according to the World Health Organization guidelines. Samples within the normal range were evaluated for sperm DNA fragmentation using the Halosperm technique. Remaining ejaculates were washed with the gradient method before cryopreservation. Sperm samples of each patient were divided equally for freezing in a cryopreservation medium with or without the antioxidant supplementation. One month later, the samples were thawed. Post-thaw total motility and DNA fragmentation were determined for each sample. Results: Semen samples of 40 patients were analyzed. We observed decreased total motility (34.8 ±5.32 % vs. 65.5 ±6.42 %, P= 0.002) and increased sperm DNA fragmentation (52.3±5.42 % vs. 26.4±3.12 %, P= 0.002) in post-thaw semen samples following cryopreservation in comparison to fresh samples. The addition of antioxidants to the freezing medium did not have a statistically significant effect on sperm motility (38.3± 6.22 % vs. 34.8 ±5.32 %, P =0.07) and DNA damage (47.5±4.7 % vs. 52.3±5.42, P =0.08) when compared to control samples following the freezing process. Conclusions: We observed increased sperm DNA fragmentation and decreased total motility following cryopreservation. No significant improvement in sperm motility or DNA integrity was obtained after the addition of 5 µM of the antioxidants taurine, ascorbic acid, and glutathione to the freezing media.