Efficacy of cryopreservation of embryos generated by intracytoplasmic sperm injection with spermatozoa from frozen testicular tissue

Failed sperm retrieval from severely oligospermic or non-obstructive azoospermic patients on oocyte retrieval day: Emergent oocyte cryopreservation is a feasible strategy

Purpose

Unexpected sperm retrieval failure on the day of oocyte retrieval is not common but frequently happened in patients with severe oligospermia or non-obstructive azoospermia(NOA). Oocyte cryopreservation is a common strategy after failed collection of sperm when concurrent ovarian stimulation is underwent. However, the use of oocyte vitrification in such male-infertility cases remains unclear.

Objective

To investigate the outcomes of emergent oocyte cryopreservation after failed sperm retrieval from severe oligospermic or non-obstructive azoospermic (NOA) patients on oocyte retrieval day.

Methods

Design: Retrospective cohort study

Setting: Academic fertility center at Lee Women's Hospital, Taiwan, between March 2015 and August 2017.

Patients: For 203 couples with NOA(n = 200) or severe oligospermia(n = 3), testicular spermatozoa (n = 67 cycles) or frozen donor sperm (n = 209 cycles) were injected into fresh or frozen-thawed oocytes via 276 intracytoplasmic sperm injection (ICSI) cycles.

Main Outcome Measures: Clinical pregnancy and live-birth rates (LBRs).

Results

In the 67 cycles involving the use of fresh testicular spermatozoa, no significant differences were observed between fresh and warmed oocytes with respect to the fertilization rates (69.2% vs. 74.1%; p = 0.27), number of Day-3 embryos (8.6±4.4 vs. 6.4±3.4; p = 0.08), number of good-quality Day-3 embryos (4.5±3.9vs. 4.7±3.0; p = 0.45), implantation rates (29.1% vs. 17.8%; p = 0.21), clinical pregnancy rates (36.4% vs. 26.8.0%; p = 0.81), live birth rates (36.4% vs. 14.3%; p = 0.46), or perinatal outcomes. In the 209 cycles involving the use of frozen donor sperm, no significant differences were seen between the two groups, except that the mean birth weights were significantly lower with fresh oocyte pregnancies than with warmed oocytes (2952±196 gm vs 2643±700 gm; p = 0.006).

Conclusions

Emergent oocyte cryopreservation is a feasible strategy to manage unexpected sperm retrieval failure from severe oligospermic or NOA patients on the oocyte retrieval day. There is no detrimental effect on the live birth rate when testicular spermatozoa or frozen donor sperm are injected into the thawed oocytes compared with fresh oocytes.

Modern human sperm freezing: Effect on DNA, chromatin and acrosome integrity

OBJECTIVE

Presence of vitrification method in sperm freezing and the introduction of solid surface vitrification beside rapid freezing in vapour, opens an easy and safe way to help infertility centres. While the effects of cryopreservation on motility, morphology and viability of sperm are documented, the question of the probable alteration of sperm DNA, chromatin and acrosome integrity after freezing and thawing procedures in different methods is still controversial.

MATERIALS AND METHODS

Normal sample were collected according to WHO strict criteria. Sperm suspensions were mixed 1:1 with 0.5 M sucrose and divided into four equal aliquots for freezing: fresh, nitrogen direct immersion vitrification (Vit), solid surface vitrification (SSV) and in vapour (Vapour). Sperm suspensions were transferred into a 0.25 ml sterile plastic. Then straw was inserted inside the 0.5 ml straw. For thawing, the straws were immersed in a 42 °C water bath. Beside the sperm parameters, we assessed the acrosome reaction by double staining, chromatin integrity by toluidine blue (Tb) and chromomycin A3 (CMA3) and DNA integrity by terminal deoxynucleotidyl transferase dUTP nick end labelling (TUNEL) respectively.

RESULTS

In progressive motility, the highest rate occurred in Vit (39.9 ± 13.3). Moreover, the lowest rate of immotile sperm was in Vit (32.7 ± 16.3). In normal morphology, the group Vit was similar to the fresh, while SSV and Vapour were significantly different from the fresh. The percentage of acrosome-reacted sperms was more in Vit (81.3 ± 10.2) than the fresh group. TUNEL+ results showed that DNA fragmentation was significantly increased in Vit (p-value = 0.025). While in SSV and Vapour results were comparable to fresh. There was a significant correlation between TUNEL+ and normal morphology, TB, CMA3 and presence of intact acrosome.

CONCLUSION

Sperm in Vapour was healthier in terms of DNA, chromatin and acrosome integrity. In contrast of higher motility and normal morphology; DNA, chromatin and acrosome integrity were decreased in Vit. However, these findings were more acceptable in SSV or Vapour.

A new insight into male fertility preservation for patients with completely immotile spermatozoa

BACKGROUND

Sperm cryopreservation is the most effective method to preserve male fertility but this is normally used for motile spermatozoa. Thus, only motile spermatozoa are used for cryopreservation in most reproductive medicine centers worldwide. The immotile spermatozoa from some problematic patients are usually discarded, resulting in a missed opportunity of sterility cryopreservation for future assisted reproductive treatments. Many studies have shown that successful fertilization can be obtained after selection of viable sperm from the completely immotile spermatozoa before ICSI. Whether the completely immotile spermatozoa are worth of freezing has not been realized The aim of this study is to explore the clinical value of cryopreservation of immotile spermatozoa.

METHODS

Completely immotile spermatozoa were collected and frozen, and subsequently viable but immotile frozen-thawed spermatozoa were selected by laser plus for ICSI. Main outcomes included spermatozoa survival index, fertilization rate and good quality embryo rate.

RESULTS

After identification by laser, the fresh samples of spermatozoa presented with a mean survival rate of 54.86% and 26.05%, and this was reduced to 44.13% and 18.13% in frozen-thawed spermatozoa samples, which showed a frozen-thawed spermatozoa survival index of 0.80 and 0.70 in the testicular and ejaculate sperm, respectively. There were no statistically differences in fertilization rate (80% vs80.51%, 75.00% vs 81.48%), cleavage rate (95.45% vs 98.95%, 100.00% vs 95.45%) and good quality embryo rate (40.48% vs 52.13%, 33.33%vs38.10%) between the frozen-thawed immotile spermatozoa group and the routine fresh immotile spermatozoa ICSI group in both testicular and ejaculate sperm, respectively.

CONCLUSIONS

The results of the study show that completely immotile spermatozoa can be frozen in order to preserve male fertility as long as viable spermatozoa are present. This procedure provides a further possibility for fertility preservation for patients with completely immotile spermatozoa.

Paternal age as an independent factor does not affect embryo quality and pregnancy outcomes of testicular sperm extraction-intracytoplasmic sperm injection in azoospermia

This study was performed to evaluate the independent influence of paternal age affecting embryo development and pregnancy using testicular sperm extraction (TESE)-intracytoplasmic sperm injection (ICSI) in obstructive azoospermia (OA) and nonobstructive azoospermia (NOA). Paternal patients were divided into the following groups: ≤30 years, 31-35 years, 36-40 years, 41-45 years and ≥46 years. There were no differences in the rates of fertilisation or embryo quality according to paternal and maternal age. However, clinical pregnancy and implantation rates were significantly lower between those ≥46 years of paternal age compared with other age groups. Fertilisation rate was higher in the OA than the NOA, while embryo quality, pregnancy and delivery results were similar. Clinical pregnancy and implantation rates were significantly lower for patients ≥46 years of paternal age compared with younger age groups. In conclusion, fertilisation using TESE in azoospermia was not affected by the independent influence of paternal age; however, as maternal age increased concomitantly with paternal age, rates of pregnancy and delivery differed between those with paternal age <41 years and ≥46 years. Therefore, paternal age ≥46 years old should be considered when applying TESE-ICSI in cases of azoospermia, and patients should be advised of the associated low pregnancy rates.

Effects of maternal age on embryo quality and pregnancy outcomes using testicular sperm with intracytoplasmic sperm injection

Objective

The aim of this study was to evaluate the influence of maternal age on fertilization, embryo quality, and clinical pregnancy in patients undergoing intracytoplasmic sperm injection (ICSI) using testicular sperm from partners with azoospermia.

Methods

A total of 416 ICSI cycles using testicular spermatozoa from partners with obstructive azoospermia (OA, n=301) and non-obstructive azoospermia (NOA, n=115) were analyzed. Female patients were divided into the following age groups: 27 to 31 years, 32 to 36 years, and 37 to 41 years. The rates of fertilization, high-quality embryos, clinical pregnancy, and delivery were compared across maternal age groups between the OA and NOA groups.

Results

The rates of fertilization and high-quality embryos were not significantly different among the maternal age groups. Similarly, the clinical pregnancy and delivery rates were not significantly different. The fertilization rate was significantly higher in the OA group than in the NOA group (p<0.05). Age-group analysis revealed that the fertilization and high-quality embryo rates were significantly different between the OA and NOA groups in patients aged 27 to 31 years old, but not for the other age groups. Although the clinical pregnancy and delivery rates differed between the OA and NOA groups across all age groups, significant differences were not observed.

Conclusion

In couples using testicular sperm from male partners with azoospermia, pregnancy and delivery outcomes were not affected by maternal age. However, women older than 37 years using testicular sperm from partners with azoospermia should be advised of the increased incidence of pregnancy failure.