Comparison of Cryopreserved Human Sperm between Ultra Rapid Freezing and Slow Programmable Freezing: Effect on Motility, Morphology and DNA Integrity
Pattama Tongdee MD*, Matchuporn Sukprasert MD**, Chonticha Satirapod MD**, Anna Wongkularb PhD**, Wicharn Choktanasiri MD**
Affiliation : * School of Obstetrics and Gynecology, Institute of Medicine, Suranaree University of Technology, Nakhon Ratchasima, Thailand ** Department of Obstetrics and Gynecology, Faculty of Medicine, Ramathibodi Hospital, Mahidol University, Bangkok, Thailand
Background : Cryopreservation of sperm is common methods to preserve male fertility. Sperm freezing, suggest slow
programmable freezing caused lower change of sperm morphology than sperm freezing in vapor of liquid nitrogen. Ultra
rapid freezing is easy to be worked on, less time, low cost and does not need high experience.
Objective : To compare the effect on sperm motility, morphology and DNA integrity of post-thawed sperm after ultra rapid
freezing and slow programmable freezing methods.
Material and Method: Experimental study at laboratory of infertility unit, Department of Obstetrics and Gynecology, Faculty
of Medicine Ramathibodi Hospital. Thirty-seven semen samples with normal semen analysis according to World Health
Organization (WHO) 1999 [normal sperm volume (>2 ml) and normal sperm concentration (>20x106/ml) and sperm
motility (>50%)]. Semen samples were washed. Then each semen sample was divided into six cryovials. Two cryovials, 0.5
ml each, were cryopreserved by slow programmable freezing. Four 0.25 ml containing cryovials, were cryopreserved by
ultra rapid freezing method. After cryopreservation for 1 month, thawed process was carried out at room temperature. Main
outcomes are sperm motility was determined by Computer-Assisted Semen Analysis (CASA), sperm morphology was determined
by eosin-methylene blue staining and sperm DNA integrity was assessed by TUNEL assay.
Results : Sperm motility was reduced significantly by both methods, from 70.4 (9.0)% to 29.1 (12.3)% in slow programmable
freezing and to 19.7 (9.8)% in ultra rapid freezing (p<0.05). Sperm motility decreased significantly more by ultra rapid
freezing (p<0.001). The percentage of normal sperm morphology and DNA integrity were also reduced significantly by both
methods. However, no significant difference between the two methods was found (p>0.05).
Conclusion : Cryopreservation of human sperm for 1 month significantly decreased sperm motility, morphology and DNA
integrity in both methods. However, sperm motility was decreased more by ultra rapid freezing.
Keywords : Ultra rapid freezing, Slow programmable freezing, Sperm motility, Sperm morphology, Sperm DNA integrity
