Effects of very rapid versus vapor phase freezing on human sperm parameters

Abstract

The aim of the present study was to compare the effects of two freezing methods, vapor phase and very rapid freezing, with and without cryoprotectant on semen parameters in men with normal semen criteria. Cryopreservation was done on semen samples from 31 men by two methods of vapor phase freezing and very rapid freezing, with and without Test Yolk buffered glycerol (TYBG) as cryoprotectant. The motility, viability, acrosome and DNA integrity were evaluated on fresh and post-thaw samples. Post-thaw sperm progressive motility was significantly higher in the presence of TYBG in the vapor phase cryopreservation (%6.30 ± 3.74) compared with the very rapid freezing method (%2.2 ± 1.97 and %4.00 ± 2.42 in the presence and absence of TYBG, respectively). There was no significant difference in viability, acrosome status and DNA integrity between two methods in presence or absence of TYBG. The very rapid freezing method in the absence of TYBG showed better sperm motility but viability, acrosome and DNA integrity were similar to the presence of TYBG. The results show that cryopreservation of human spermatozoa together with seminal plasma by using vapor phase method is better than very rapid freezing method to preserve sperm progressive motility; however very rapid freezing method is quick and simple and do not require special cryoprotectant. It can be used for cryopreservation of small number of spermatozoa in IVF centers.

Enolase1 (ENO1) and glucose-6-phosphate isomerase (GPI) are good markers to predict human sperm freezability

“…⁄⁄ Significant differences are indicated at P < 0.01. chemotherapy or radiotherapy, cryptozoospermia, transient azoospermia and for rare occupational reasons. In addition to its extensive usage in assisted reproduction technology, cryopreservation can impair sperm DNA integrity, motility, viability, etc., [6,4], resulting in reduced sperm fertility. Various studies sought to find freezability markers to predict the ejaculate freezability and progress has been made.…”

“…It is of great importance for some infertile patients like cancer patients about to undergo chemotherapy or radiotherapy, patients with defective genitals and patients with oligozoospermia or asthenospermia. But it adversely affects the sperm in terms of standard sperm evaluation parameters and fertilizing ability [6,4]. To date, freezability success of sperm samples is unpredictable.…”

Cryopreservation of human spermatozoa with minimal non-permeable cryoprotectant

“…A minimum of 200 sperm per replicate was counted and the numbers of motile and immotile sperm were recorded. Recovered motility was calculated as a percentage of post thaw motility divided by pre-freeze motility [10,21]. Pre-freeze motility is the motility obtained after Percoll separation.…”

Multivariate model for predicting semen cryopreservation outcomes in a human sperm bank

“…However, cryopreservation can reduce sperm fertility through impairing sperm DNA integrity, motility and viability 23. Many studies on human and animal semen have attempted to define predictors of freezability.…”

“…However, cryopreservation adversely affects spermatozoa in terms of standard semen parameters and fertilizing ability 23. The recovery of functionally intact spermatozoa from thawed samples varies between individuals and is dependent on the cryopreservation process but also on the initial quality of the semen sample.…”