Movement characteristics of human epididymal sperm used for fertilization of human oocytes in vitro.
OBJECTIVE
To develop mathematical models using kinematic parameters from Computer-Aided Sperm Analysis (CASA) that predict the fertilization rate of sperm recovered from the caput epididymidis and to test the hypothesis that fertilization was enhanced by the presence of specific sperm subpopulations in the inseminate.


METHODS
In vitro fertilization (IVF) program.


METHODS
Thirteen patients with congenital absence of the vas deferens provided epididymal sperm for IVF as well as for CASA.


RESULTS
The mathematical model that was most predictive of fertilization rates included kinematic parameters of the epididymal aspirate (percent motility), the inseminate used for IVF (curvilinear velocity [VCL]), and the change in sperm movement after in vitro processing by the mini-Percoll technique (difference in amplitude of lateral head displacement [ALH]). Multivariate cluster analysis revealed that inseminates that resulted in higher fertilization rates had subpopulations of sperm that were characterized by high VCL and high mean angular displacement, as well as a greater change in ALH after processing.


CONCLUSIONS
In vitro fertilization with epididymal sperm was more likely to succeed when the sperm population that was initially aspirated had a higher proportion of motile cells and when these sperm were capable of capacitation in vitro as indicated by the appearance of sperm subpopulations with motility that resembled hyperactivation.
Davis
R O
RO
Division of Reproductive Biology and Medicine, University of California, Davis 95616.
Overstreet
J W
JW
Asch
R H
RH
Ord
T
T
Silber
S J
SJ
D003936:Diagnosis, Computer-Assisted; D004822:Epididymis; D005306:Fertilization; D005307:Fertilization in Vitro; D005544:Forecasting; D006801:Humans; D008297:Male; D008954:Models, Biological; D012044:Regression Analysis; D013081:Sperm Motility