Pregnancy outcome and neonatal data of children born after intracytoplasmic sperm injection with a different duration of cryopreservation of spermatozoa obtained through testicular sperm extraction

Rapid cryopreservation of small quantities of human spermatozoa by a self-prepared cryoprotectant without animal component

Cryopreservation of small quantities of human spermatozoa whilst maintaining adequate post‐thawing motility has been found an essential challenge for male fertility preservation. Therefore, the study used an effective, and convenient rapid‐freezing method to freeze small amounts of human spermatozoa by adding self‐prepared cryoprotectant (SPC) without animal component. In the feasibility experiment, no significant differences in progressive motility, normal sperm morphology, vitality or DNA fragmentation index between the conventional slow freezing and rapid freezing were realised. The present study prospectively analysed the effects of sperm freezing and resuscitation in 175 patients with severe oligozoospermia (sperm concentration <1 × 10⁶/ml). We observed the 120 severe oligozoospermia specimens had a mean recovery rate of 60.19% ± 10.43% and a mean cryosurvival rate of 68.0% ± 9.17%. In addition, 55 cryptozoospermia specimens were analysed. The small‐volume cryopreservation showed advantages. The total sperm recovery, motility recovery and sperm loss rates were 98.48%, 50.17% and 1.52% respectively. In short, the SPC is safe and effective, and can be used to rapidly freeze severe oligozoospermia specimens. That is useful for successful sperm freezing whilst avoiding the risk of azoospermia in the later stages and promoting comprehensive fertility preservation.

Long-term sperm cryopreservation does not affect post-thaw survival rates

Objective:

To compare cryosurvival rates of human spermatozoa in a prolonged period of cryopreservation.

Methods:

This retrospective study involved 33 cryopreserved semen samples from patients with cancer, between 2002 and 2011. The semen sample was obtained by masturbation and initial semen analysis was performed. The cryoprotectant solution was added and samples were frozen in liquid nitrogen in a slow step-wise process. For thawing, the samples were incubated at 25.0ºC for 15 min, followed by incubation at 36.7ºC for 15 min. The cryosurvival rate (CS) was calculate by CS= [(% total motile sperm post-thaw) x100/(% total motile sperm/tube)]. Each study sample was divided into three aliquots (Study Group; n=23): (I) official patient sample, which was kept cryopreserved for subsequent Assisted Reproduction procedure, cryopreserved between 2002 and 2011; (II) sample destined to post-thaw tests, performed after the sample had been kept cryopreserved for 24 hours; and (III) study sample. Only in 2014, after 3-12 years of cryopreservation, the study samples were thawed and evaluated. To validate the study design, a Validation Group was created including 10 samples obtained between 2014 and 2016, using the same methodology in the study samples. The data was analyzed using the T-test, with a significant p-value of 5%.

Results:

The mean age was 29.93±9.57 years in the Study Group and 21.80±6.49 years in the Validation Group. No significant difference between the Validation and Study Groups was found in the initial semen analysis (p>0.05). After 24 hours of cryopreservation, the cryosurvival rate was 26.11±46.36% in the Study Group and 23.71±57.06% in the Validation Group. Aliquots of the same sample preserved from 3-12 years demonstrated 23.71±57.06% of cryosurvival rate. Thus, no significant difference was found vis-à-vis the cryosurvival rates (p=0.56).

Conclusion:

We concluded that the method introduced in the late 1990s, which enables the removal of debris, potentially toxic elements and generators of reactive oxygen species from the seminal sample before cryopreservation, exhibited efficiency in maintaining the same cryosurvival rate after an extended period.

A novel micro-straw for cryopreservation of small number of human spermatozoon

Cryopreservation of few spermatozoa is still a major challenge for male fertility preservation. This study reports use a new micro-straw (LSL straw) for freezing few spermatozoa for intracytoplasmic sperm injection (ICSI). Semen samples from 22 fertile donors were collected, and each semen sample was diluted and mixed with cryoprotectant in a ratio of 1:1, and then frozen using three different straws such as LSL straw (50–100 μl), traditional 0.25 ml and 0.5 ml straws. For freezing, all straws were fumigated with liquid nitrogen, with temperature directly reducing to −130–−140°C. Sperm concentration, progressive motility, morphology, acrosome integrity, and DNA fragmentation index were evaluated before and after freezing. After freezing-thawing, LSL straw group had significantly higher percentage of sperm motility than traditional 0.25 ml and 0.5 ml straw groups (38.5% vs 27.4% and 25.6%, P < 0.003). Sperm motility and acrosomal integrity after freezing-thawing were significantly lower than that of before freezing. However, there was no significant difference in morphology, acrosome, and DNA integrity between the three types of straws (P > 0.05). As LSL straws were thinner and hold very small volume, the freezing rate of LSL straw was obviously faster than 0.25 ml straw and 0.5 ml straws. In conclusion, LSL micro-straws may be useful to store few motile spermatozoa with good recovery of motility for patients undergoing ICSI treatment.

Effect of maternal and treatment-related factors on the prevalence of birth defects after PESA-ICSI and TESE-ICSI: a retrospective cohort study

INTRODUCTION

We performed a retrospective cohort study with the aim to evaluate the effect of maternal and treatment-related factors on the prevalence of birth defects after intracytoplasmic sperm injection (ICSI) using percutaneous epididymal sperm aspiration (PESA) and testicular sperm extraction (TESE).

MATERIAL AND METHODS

643 newborns born after PESA-ICSI (n = 406) and TESE-ICSI (n = 237) in Radboud University Medical Center, after a gestational age of 12 weeks, 1 January 2002-1 January 2011 and 1 March-1 November 2014, respectively, were included in this study. Three sources of data were used for analysis: questionnaires, national obstetrics registration forms, and a lab-database of all ICSI treatments. Data were analyzed using generalized estimating equations and logistic regression analysis.

RESULTS

The prevalence of major birth defects in newborns born after PESA-ICSI was 6.9% and after TESE-ICSI was 5.9% (odds ratio 0.89, 95% confidence interval 0.46-1.75). No significant association was found between maternal or treatment-related factors and the prevalence of birth defects.

CONCLUSIONS

We found a similar overall prevalence of birth defects in newborns born after PESA-ICSI and TESE-ICSI. The maternal and treatment-related factors investigated did not show a significantly increased cumulative risk of birth defects.