[Pre-freezing equilibration improves post-thaw human semen parameters].
OBJECTIVE
To investigate the effect of pre-freezing equilibration on the cryo-survival of human sperm and to optimize the protocol of direct fumigation for the freeze-thawing of human sperm.


METHODS
We collected 50 semen samples from healthy donors, each subjected to cryopreservation with 3 different methods: non-equilibration freezing (Group A), 10-min equilibration at room temperature before freezing (Group B), and 10-min equilibration at 4 degrees C before freezing (Group C). We examined all the post-thaw semen samples by computer-assisted semen analysis for the sperm motility parameters, and detected the sperm vitality and deformity index (SDI).


RESULTS
The recovery rate of progressive sperm motility was (61.88 +/- 16.94)% in Group C, remarkably higher than in A ([48.61 +/- 16.44]%) and B ([49.41 +/- 13.77]%) (P < 0.05), but with no significant difference between the latter two. And there were no significant differences in sperm vitality and SDI among the three groups.


CONCLUSIONS
Ten-minute equilibration at 4 degrees C before freezing can evidently improve the progressive motility of sperm in addition to its advantages of easy operation and controllable experimental condition.
Department of Urology/Laboratory of Sperm Development and Genetics , Shanghai Institute of Andrology/Shanghai Human Sperm Bank, Renji Hospital, Shanghai Jiaotong University School of Medicine, Shanghai 200001, China. medicaln@126.com
Ya-Nan
YN
Wang
Sha-Sha
SS
Zou
Qian
Q
Xiao
Yong
Y
Liu
Xiao-Rong
XR
Cao
Zheng
Z
Li
Hong-Liang
HL
Hu
D000328:Adult; D015925:Cryopreservation / Q000379:methods*; D006801:Humans; D008297:Male; D055101:Semen Analysis; D012662:Semen Preservation / Q000379:methods*; D013074:Sperm Banks; D013076:Sperm Count; D013081:Sperm Motility; D055815:Young Adult