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Updated: Aug 19, 2026
Sperm Collection of Differential Quality Using Density Gradient Centrifugation
Published on: November 29, 2018
Comparative study on density gradients and swim-up preparation techniques utilizing neat and cryopreserved
Shyam S R Allamaneni1, Ashok Agarwal, Sreedhar Rama
1Center for Advanced Research in Human Reproduction, Infertility, and Sexual Function, Glickman Urological Institute and Department of Obstetrics-Gynecology, The Cleveland Clinic Foundation, 9500 Euclid Avenue, Desk A19.1, Cleveland, OH 44195, USA.
Aim:
To 1) compare post-wash and post-thaw parameters of sperm processed with PureSperm density gradient technique and swim-up method; and 2) test the efficacy of two commonly available density gradient media PureSperm and ISolate.
Methods:
This prospective study used semen specimens from 22 patients. Specimens from nine patients were processed by both PureSperm density gradient and swim-up method. These specimens were then cryopreserved. Thirteen specimens were processed by both PureSperm (40 % and 80 %) and Isolate (50 % and 90 %) double density gradient techniques. The two fractions processed by both PureSperm and swim-up were analyzed for post-wash sperm characteristics. Post-thaw analysis was done after 24 hours. Sperm fractions obtained after processing with PureSperm and ISolate were compared for post-wash sperm characteristics and ROS levels.
Results:
Specimens prepared with PureSperm had significantly higher median total motile sperm counts (TMSC) (32.2 x 10(6) vs. 17.6 x 10(6)), recovery rates (69.2 % vs. 50.0 %), and longevity at 4 hours (83.0 % vs. 55.0 %) compared to specimen prepared by swim-up. Post-thaw specimens also had a higher recovery and longevity at 4 hours with PureSperm as compared to the swim-up. Semen specimens processed by PureSperm had significantly higher total sperm count, TMSC, and percentage recovery rates (30.0 % vs. 19.7 %) than ISolate.
Conclusion:
Semen quality is better preserved in fresh and cryopreserved semen prepared with PureSperm density gradient compared to swim-up. A significant enrichment of sperm is observed with PureSperm compared to ISolate. Higher recovery rates of mature motile sperm obtained after PureSperm sperm preparation may be beneficial for successful ART.
