[Effect of vitrification on sperm parameters and apoptosis in fertile men]

ABSTRACT

Today, cryopreservation of the human sperm is a common technique for treating infertility. It has been indicated that cryopreservation by different methods decrease the sperm motility and viability in fertile men, but still effect of freezing of the sperm by vitrification method have not been evaluated on sperm parameters and apoptosis. The aim of this study was to evaluate the effect of vitrification of sperm of fertile men on different sperm parameters [motility, morphology, viability and count[and apoptosis after thawing. In this experimental study which was conducted at Yazd Infertility Research and Clinical Center in 2009, seventeen semen samples were collected by masturbation from people who came to this centre. Semen analysis was performed according to WHO standards. Smear was provided from these samples and fixed for TUNEL staining. Some samples were directly cryopreserved by cryoloope in liquid nitrogen and stored at least for Seven days. After thawing, samples were evaluated for sperm parameters. The collected data was analyzed by the SPSS software using paired T-test and Willcoxon statistical test. The progressive movement of sperm was significantly decreased by vitrification. Also significant decrease in viability and morphology of the sperm and increase in the rate of apoptosis was observed after vitrification. The amount of apoptosis had negatively correlated with normal parameters of spermatozoa [especially progressive motility and viability]. These results indicated that vitrification is harmful for sperm parameters and of apoptosis rate in fertile men. However, the apoptosis rate was lower compared to other freezing methods: