Effect of cryopreservation on human sperm motility, vitality and dna integrity in fresh and processed sperms

الملخص EN

Objective : To investigate the effects of cryopreservation on sperm motility, vitality and DNA integrity in fresh and processed sperms.

Design : Pre-cryopreservation and post-cryopreservation analysis of sperm vitality, motility and DNA integrity in fresh and processed semen.

Setting : Department of Dermatology, Venereology and Androlog, in coordination with the Department of Clinical Pathology Assiut University Hospital.

Patients : 50 fertile men (within the last year) who are clinically free and with normal semen parameters the semen samples collected by masturbation into sterile containers after at least 3 days of sexual abstinence.

Interventions : Semen evaluation for, conventional semen analysis, sperm vitality with Hypo-Osmotic Swelling, esi (HOS), sperm DNA integrity by flowcytometry.

Each sample was divided into 2 halves : The first half was cryoperserved without processing.

The second half of the sample was processed by swim up technique HOS test, percentage of progressive motility and DNA integrity after processing.

Cryopreservation in liquid nitrogen for at least 24 hours for all samples (fresh and processed) was done.

HOS test, percentage of progressive motility and DNA integrity after thawing for all samples (fresh and processed).

Main outcome measures : Sperm DNA fragmentation index was determined using flow cytometry, sperm vitality was determined using HOS test and percentage of progressive sperm motility was determined using light microscopic examination according to criteria of WHO (1999).

Results : Sperm frozen after processing had higher resistance to freezing damage as regards vitality and motility when compared with sperm frozen without processing however, sperm DNA fragmentation index was more in frozen processed than unprocessed sperms.

Conclusions : Cryopreservation results in decreased sperm vitality, motility and increased sperm DNA fragmentation.

Freezing processed sperm give better post-thawing vitality and motility but, increased sperm DNA fragmentation when compared with unprocessed sperm.