Comparison of intracytoplasmic sperm injection outcome with fresh versus frozen-thawed testicular sperm in men with nonobstructive azoospermia: a systematic review and meta-analysis

ICSI outcome after microdissection testicular sperm extraction, testicular sperm aspiration and ejaculated sperm

We conducted a case-controlled single-center cohort study to evaluate the intracytoplasmic sperm injection (ICSI) outcome in severe male infertility with different methods of sperm obtention. The data was compiled from a tertiary university hospital. The micro-TESE procedures were performed from 2008 to 2023, with a sperm recovery rate (SRR) of 45 %. The ICSI treatments were carried out between 2011 and 2023. The aim of the study was to compare the ICSI outcome using sperm obtained by microdissection testicular extraction (micro-TESE), testicular sperm aspiration (TESA), and ejaculated sperm with sperm concentration less than 15 million per milliliter. We included a total of 462 ICSI cycles, of which 340 ICSIs with ejaculated sperm of men with oligozoospermia, with or without asthenozoospermia or teratozoospermia (OAT group), 51 ICSIs with TESA sperm of men with obstructive azoospermia (OA, TESA group), and 71 ICSIs with micro-TESE sperm of men with non-obstructive azoospermia (NOA, micro-TESE group). The patient characteristics, fertilization rate, pregnancy rate, and pregnancy outcome data were similar between the groups. The fertilization rates were 66.0 % in the OAT group, 68.3 % in the TESA group and 62.8 % in the micro-TESE group and live birth rate per embryo transfer were 23.7 %, 28.9 %, and 25.0 %, respectively, without statistical difference. The obstetrical outcome was similar in all the groups. The overall clinical results in all ICSI cycles performed for treating severe male factor infertility were similar, independent of the method of collection of spermatozoa. The results also confirm the efficacy of micro-TESE in the treatment of severe male factor infertility.

Financial decision analysis based on "willingness to pay" for surgical sperm retrieval approaches among men with non-obstructive azoospermia in the United States

OBJECTIVE

To determine the most financially optimal surgical approach for testicular sperm retrieval for men with non-obstructive azoospermia.

DESIGN

A decision tree was created examining five potential surgical approaches for men with non-obstructive azoospermia pursuing one cycle of intracytoplasmic sperm injection. An expected financial net loss was determined for each surgical option based on couples' willingness to pay for one cycle of intracytoplasmic sperm injection resulting in pregnancy. The branch with the lowest expected net loss was defined as the most optimal financial decision (minimizing loss to a couple). Fresh testicular sperm extraction implied testicular sperm extraction was performed in conjunction with programmed ovulation induction. Frozen testicular sperm extraction implied testicular sperm extraction was performed initially, and ovulation induction/intracytoplasmic sperm injection was canceled if sperm retrieval failed.  The surgical options included fresh conventional testicular sperm extraction, with and without "back-up" sperm cryopreservation, fresh microsurgical testicular sperm extraction, with and without "back-up" sperm cryopreservation, and frozen microsurgical testicular sperm extraction. Success was defined as pregnancy after one intracytoplasmic sperm injection cycle.

MATERIALS AND METHODS

Probabilities of successful sperm retrieval with conventional testicular sperm extraction/microsurgical testicular sperm extraction, post-thaw sperm cellular loss following frozen microsurgical testicular sperm extraction, ovulation induction/intracytoplasmic sperm injection cycle out-of-pocket costs, intracytoplasmic sperm injection pregnancy rates for men with non-obstructive azoospermia, standard conventional testicular sperm extraction cost and average willingness to pay for intracytoplasmic sperm injection cycle were gathered from the systematic literature review. Costs were in USD and adjusted to inflation (as of April 2020). Two-way sensitivity analysis was performed on varying couples' willingness to pay for one cycle of intracytoplasmic sperm injection and varying microsurgical testicular sperm extraction out-of-pocket costs.

RESULTS

According to our decision tree analysis (assuming minimum microsurgical testicular sperm extraction cost of $1,000 and willingness to pay of $8,000), the expected net loss for each branch was as follows: -$17,545 for fresh conventional testicular sperm extraction, -$17,523 for fresh microsurgical testicular sperm extraction, -$9,624 for frozen microsurgical testicular sperm extraction, -$17,991 for fresh conventional testicular sperm extraction with "backup", and -$18,210 for fresh microsurgical testicular sperm extraction with "backup". Two-way sensitivity analysis with a variable willingness to pay values and microsurgical testicular sperm extraction and in-vitro fertilization costs confirmed that frozen microsurgical testicular sperm extraction consistently presented the lowest net loss compared to other options. Interestingly, when directly comparing fresh microsurgical testicular sperm extraction and conventional testicular sperm extraction with "back-up", scenarios with decreasing willingness to pay and lower microsurgical testicular sperm extraction costs demonstrated fresh conventional testicular sperm extraction with "back-up" as more optimal than fresh microsurgical testicular sperm extraction with "back-up".

CONCLUSIONS

For those couples who must pay out of pocket, our study suggests that frozen microsurgical testicular sperm extraction is the most financially optimal decision for the surgical management of non-obstructive azoospermia, regardless of microsurgical testicular sperm extraction cost and the couple's willingness to pay.

Novel predictors for livebirth delivery rate in patients with idiopathic non-obstructive azoospermia based on the clinical prediction model

Objective

To build a prediction model for live birth delivery per intracytoplasmic sperm injection (ICSI) in iNOA patients by obtaining sperm by microdissection testicular sperm extraction (mTESE).

Methods

A retrospective cohort study of 377 couples with iNOA male partners treated with 519 mTESE-ICSI cycles was conducted from September 2013 to July 2021 at the Reproductive Medical Centre of Peking University Third Hospital. Following exclusions, 377 couples with iNOA male partners treated with 482 mTESE-ICSIs were included. A prediction model for live birth delivery per ICSI cycle was built by multivariable logistic regression and selected by 10-fold cross-validation. Discrimination was evaluated by c-statistics and calibration was evaluated by the calibration slope.

Results

The live birth delivery rate per mTESE-ICSI cycle was 39.21% (189/482) in these couples. The model identified that the presence of motile sperm during mTESE, bigger testes, higher endometrial thickness on the day of human chorionic gonadotrophin (hCG) administration (ET-hCG), and higher quality embryos are associated with higher live birth delivery success rates. The results of the model were exported based on 10-fold cross-validation. In addition, the area under the mean ROC curve was 0.71 ± 0.05 after 10-fold cross-validation, indicating that the prediction model had certain prediction precision. A calibration plot with an estimated intercept of -1.653 (95% CI: -13.403 to 10.096) and a slope of 1.043 (95% CI: 0.777 to 1.308) indicated that the model was well-calibrated.

Conclusion

Our prediction model will provide valuable information about the chances of live birth delivery in couples with iNOA male partners who have a plan for mTESE-ICSI treatment. Therefore, it can improve and personalize counseling for the medical treatment of these patients.

Clinical and neonatal outcomes of using a modified micro cryotube for cryopreservation of small numbers of spermatozoa for TESA-ICSI cycles

Cryopreservation of a small number of human spermatozoa is still a major challenge for embryologists. The aim of this study was to evaluate the clinical pregnancy and neonatal outcomes of intracytoplasmic sperm injection (ICSI) using a modified micro cryotube as freezing carrier for freezing small numbers of human spermatozoa collected by testicular sperm aspiration (TESA). We conducted a retrospective study to analyses the ICSI outcomes of using frozen-thawed few testicular spermatozoa in males with obstructive azoospermia (OA) from June 2017 to June 2021. Of 155 ICSI treatment cycles, 79 cycles were allocated to frozen sperm group and a modified micro cryotube was used for freezing testicular sperm, 76 cycles were allocated as fresh sperm group. No significant differences were observed in fertilization rate, good quality embryo rate, and blastocyst rate between the frozen sperm group and fresh sperm group (P > 0.05). Similarly, in the fresh embryo transfer cycles plus the first frozen-thawed embryo transfer cycles, the total clinical pregnancy rate (54.43% vs 57.89%), implantation rate (46.08% vs 49.47%), miscarriage rate (13.95% vs 13.64%) and live birth rate (45.57% vs 48.68%) were not statistically different between the frozen and fresh sperm groups (P > 0.05). In addition, there was no statistical differences in the mean gestational age (38.33weeks ± 1.74 vs 37.89weeks ± 1.87), preterm delivery rate (5.56% vs 10.81%), mean birth weight at delivery (3026.50 g ± 577.64 vs 2977.56 g ± 528.93), and low birth weight (12.50% vs 19.51%) between the two groups (P > 0.05 in all cases). Modified micro cryotube for cryopreservation of rare testicula rretrieved spermatozoa did not negatively affect the pregnancy and neonatal outcomes in TESA-ICSI cycles. The presented method may be a useful alternative for cryopreservation of small numbers of human spermatozoa in clinical setting.

The impact of cryopreserved sperm on intrauterine insemination outcomes: is frozen as good as fresh?

Introduction

Frozen sperm utilization might negatively impact cycle outcomes in animals, implicating cryopreservation-induced sperm damage. However, in vitro fertilization and intrauterine insemination (IUI) in human studies are inconclusive.

Methods

This study is a retrospective review of 5,335 IUI [± ovarian stimulation (OS)] cycles from a large academic fertility center. Cycles were stratified based on the utilization of frozen (FROZEN, n = 1,871) instead of fresh ejaculated sperm (FRESH, n = 3,464). Main outcomes included human chorionic gonadotropin (HCG) positivity, clinical pregnancy (CP), and spontaneous abortion (SAB) rates. Secondary outcome was live birth (LB) rate. Odds ratios (OR) for all outcomes were calculated utilizing logistic regression and adjusted (adjOR) for maternal age, day-3 FSH, and OS regimen. Stratified analysis was performed based on OS subtype [gonadotropins; oral medications (OM): clomiphene citrate and letrozole; and unstimulated/natural]. Time to pregnancy and cumulative pregnancy rates were also calculated. Further subanalyses were performed limited to either the first cycle only or to the partner's sperm only, after excluding female factor infertility, and after stratification by female age (<30, 30-35, and >35 years old).

Results

Overall, HCG positivity and CP were lower in the FROZEN compared to the FRESH group (12.2% vs. 15.6%, p < 0.001; 9.4% vs. 13.0%, p < 0.001, respectively), which persisted only among OM cycles after stratification (9.9% vs. 14.2% HCG positivity, p = 0.030; 8.1% vs. 11.8% CP, p = 0.041). Among all cycles, adjOR (95% CI) for HCG positivity and CP were 0.75 (0.56-1.02) and 0.77 (0.57-1.03), respectively, ref: FRESH. In OM cycles, adjOR (95% CI) for HCG positivity [0.55 (0.30-0.99)] and CP [0.49 (0.25-0.95), ref.: FRESH] favored the FRESH group but showed no differences among gonadotropin and natural cycles. SAB odds did not differ between groups among OM and natural cycles but were lower in the FROZEN group among gonadotropin cycles [adjOR (95% CI): 0.13 (0.02-0.98), ref.: FRESH]. There were no differences in CP and SAB in the performed subanalyses (limited to first cycles or partner's sperm only, after excluding female factors, or after stratification according to female age). Nevertheless, time to conception was slightly longer in the FROZEN compared to the FRESH group (3.84 vs. 2.58 cycles, p < 0.001). No significant differences were present in LB and cumulative pregnancy results, other than in the subgroup of natural cycles, where higher LB odds [adjOR (95% CI): 1.08 (1.05-1.12)] and higher cumulative pregnancy rate (34% vs. 15%, p = 0.002) were noted in the FROZEN compared to the FRESH group.

Conclusion

Overall, clinical outcomes did not differ significantly between frozen and fresh sperm IUI cycles, although specific subgroups might benefit from fresh sperm utilization.

The Renaissance of Male Infertility Management in the Golden Age of Andrology

Infertility affects nearly 186 million people worldwide and the male partner is the cause in about half of the cases. Meta-regression data indicate an unexplained decline in sperm concentration and total sperm count over the last four decades, with an increasing prevalence of male infertility. This suggests an urgent need to implement further basic and clinical research in Andrology. Andrology developed as a branch of urology, gynecology, endocrinology, and, dermatology. The first scientific journal devoted to andrological sciences was founded in 1969. Since then, despite great advancements, andrology has encountered several obstacles in its growth. In fact, for cultural reasons, the male partner has often been neglected in the diagnostic and therapeutic workup of the infertile couple. Furthermore, the development of assisted reproductive techniques (ART) has driven a strong impression that this biotechnology can overcome all forms of infertility, with a common belief that having a spermatozoon from a male partner (a sort of sperm donor) is all that is needed to achieve pregnancy. However, clinical practice has shown that the quality of the male gamete is important for a successful ART outcome. Furthermore, the safety of ART has been questioned because of the high prevalence of comorbidities in the offspring of ART conceptions compared to spontaneous conceptions. These issues have paved the way for more research and a greater understanding of the mechanisms of spermatogenesis and male infertility. Consequently, numerous discoveries have been made in the field of andrology, ranging from genetics to several "omics" technologies, oxidative stress and sperm DNA fragmentation, the sixth edition of the WHO manual, artificial intelligence, management of azoospermia, fertility in cancers survivors, artificial testis, 3D printing, gene engineering, stem cells therapy for spermatogenesis, and reconstructive microsurgery and seminal microbiome. Nevertheless, as many cases of male infertility remain idiopathic, further studies are required to improve the clinical management of infertile males. A multidisciplinary strategy involving both clinicians and scientists in basic, translational, and clinical research is the core principle that will allow andrology to overcome its limits and reach further goals. This state-of-the-art article aims to present a historical review of andrology, and, particularly, male infertility, from its "Middle Ages" to its "Renaissance", a golden age of andrology.

Sperm cryopreservation does not affect live birth rate in normozoospermic men: analysis of 7969 oocyte donation cycles

STUDY QUESTION

Does sperm cryopreservation influence the reproductive outcomes of normozoospermic patients in oocyte donation cycles?

SUMMARY ANSWER

After controlling for confounders, the use of cryopreserved semen from normozoospermic patients does not affect pregnancy and live birth rates after elective ICSI.

WHAT IS KNOWN ALREADY

Sperm cryopreservation by slow freezing is a common practice in ART. While frozen-thawed semen typically presents reduced motility and vitality, its use for ICSI is generally considered adequate in terms of reproductive outcomes. Nevertheless, most studies comparing reproductive outcomes between fresh and cryopreserved sperm include patients with severe male factor (testicular sperm, oligo-, and/or asthenozoospermia) or women of advanced maternal age, where the altered quality of the gametes can partially mask the full effect of freezing/thawing.

STUDY DESIGN, SIZE, DURATION

The study included a retrospective cohort of 7969 couples undergoing their first oocyte donation cycle between January 2013 and December 2019 in one large clinic, using normozoospermic semen from the male partner. All cycles involved elective ICSI, fresh oocytes, and a fresh embryo transfer, either at cleavage or blastocyst stage. Two study groups were established based on the sperm status: fresh (n = 2865) and cryopreserved (n = 5104).

PARTICIPANTS/MATERIALS, SETTING, METHODS

A slow freezing protocol was used for all sperm cryopreservation. Sperm washing, capacitation, and selection prior to ICSI were performed identically for fresh and frozen-thawed samples, using pellet swim-up. Fertilization rate (FR), pregnancy (biochemical and ongoing), and live birth rates were compared between study groups using univariate and multivariate regression analyses.

MAIN RESULTS AND THE ROLE OF CHANCE

Male and female age, sperm concentration and motility after ejaculation, and number of oocytes inseminated were similar between cycles using fresh or cryopreserved sperm. Analysis by Student's t-test did not indicate a significant difference in FR between fresh and cryopreserved sperm (P = 0.0591); however, after adjusting for confounders, this difference reached statistical significance: 74.65% FR for fresh (CI 95%: 73.92-75.38) versus 73.66% for cryopreserved sperm (CI 95%: 73.11-74.20), P = 0.0334. The adjusted regression analysis revealed higher odds of biochemical pregnancy when using fresh sperm (odds ratio (OR): 1.143, P = 0.0175), but no significant effects of sperm cryopreservation were observed for ongoing pregnancy (OR: 1.101, P = 0.0983) and live birth (OR: 1.082, P = 0.1805).

LIMITATIONS, REASONS FOR CAUTION

Caution should be exerted when extrapolating these results to different protocols for sperm cryopreservation and selection, or to IVM, advanced maternal age and classical IVF cycles, which were excluded from analysis. Owing to the retrospective nature of the study, some uncontrolled for variables may affect the results.

WIDER IMPLICATIONS OF THE FINDINGS

Sperm cryopreservation does not affect pregnancy and live birth rates in normozoospermic patients, and although it may lower FR s slightly, this would not be clinically relevant. In line with previous studies that included patients with an apparent male or female factor, sperm cryopreservation is a safe and convenient technique.

STUDY FUNDING/COMPETING INTEREST(S)

The study received no external funding and all authors have no conflicts of interest to declare.

TRIAL REGISTRATION NUMBER

N/A.

Feasibility of repeat microdissection testicular sperm extraction within 6 months for nonobstructive azoospermia

BACKGROUND

Microdissection testicular sperm extraction (mTESE) is the mainstay of sperm retrieval in men with nonobstructive azoospermia (NOA). Some experts believe that a resting period of ≥6 months is required between procedures to ensure better sperm retrieval rates and fewer complications. However, no scientific studies have investigated how long patients should wait before arranging a second mTESE procedure. This retrospective study aimed to evaluate whether good success rates are still achieved when a repeat mTESE procedure is performed within 6 months.

METHODS

Total 146 patients with NOA who underwent mTESE twice from the same testis between May 2012 and September 2019 were retrospectively collected. These patients were categorized into three groups according to the time interval between the two mTESE surgeries, with 44, 60, and 42 patients undergoing a repeat mTESE after <3 months (group I), between 3 and 6 months (group II), and >6 months (group III) after the first procedure, respectively.

RESULTS

No significant differences were observed between groups in terms of patient characteristics and preoperative hormone profiles. Overall sperm retrieval rates did not differ among the three groups (93.2%, 90.0%, and 88.1% in groups I, II, and III, respectively [ p = 0.719]), nor did fertility outcomes, including rates of fertilization, biochemical pregnancy, clinical pregnancy, and cumulative live births.

CONCLUSION

Sperm retrieval rates for repeat mTESE procedures were consistently high, even when the second procedure was performed within 6 months of the first. Repeat mTESE within 6 months is not a limitation for patients with NOA, if required clinically.

What Does Intracytoplasmic Sperm Injection Change in Embryonic Development? The Spermatozoon Contribution

The intracytoplasmic sperm injection (ICSI) technique was invented to solve severe male infertility due to altered sperm parameters. Nowadays, it is applied worldwide for the treatment of couple infertility. ICSI is performed with any available spermatozoon from surgery or ejaculated samples, whatever are the sperm motility, morphology or quantity. The aim of the present review was to study if embryo development and kinetics would be modified by (1) ICSI under the technical aspects, (2) the micro-injected spermatozoa in connection with male infertility. From published data, it can be seen that ICSI anticipates the zygote kinetics Furthermore, because fertilization rate is higher in ICSI compared to conventional in vitro fertilization (IVF), more blastocysts are obtained for clinical use in ICSI. Sperm and spermatozoa characteristics, such as sperm parameters, morphology and vitality, DNA content (levels of sperm DNA fragmentation, microdeletions, and chromosomal abnormalities), RNA content, epigenetics, and sperm recovery site (testicular, epididymis, and ejaculated), have an impact on fertilization and blastocyst rates and embryo kinetics in different ways. Even though ICSI is the most common solution to solve couples' infertility, the causes of male infertility are crucial in building a competent spermatozoa that will contribute to normal embryonic development and healthy offspring.

Optimizing outcomes for men with severe infertility

PURPOSE OF REVIEW

To evaluate recent evidence related to optimizing outcomes for men with severe infertility, including effect of ejaculatory abstinence interval on semen parameters and assisted reproductive technology (ART) outcomes, and impact of cryopreservation on surgically retrieved testicular sperm obtained from men with nonobstructive azoospermia (also referred to as azoospermia due to spermatogenic dysfunction).

RECENT FINDINGS

Recent evidence strongly suggests that a short abstinence interval improves sperm motility and ART outcomes. Similarly, recent studies have concluded that using fresh vs. frozen testicular sperm results in higher live birth rates.

SUMMARY

Although the World Health Organization currently recommends a 2- to 7-day ejaculatory abstinence period, this interval is based more on the need to standardize semen parameters than clinical outcomes. In fact, recent evidence suggests that shorter abstinence consistently improves sperm motility and ART outcomes for infertile men. Similarly, recent studies have reported an improvement in live birth rates with fresh (vs. frozen) testicular sperm, though their retrospective design and lack of intention to treat analyses makes it difficult to draw strong conclusions. Although additional, well designed studies are needed, providers may be able to leverage these techniques in their practice to improve outcomes for some infertile men.

Extended culture of cleavage embryo to blastocyst embryo is among the good predictors of successful outcome in vitrified-thawed ICSI cycles

Background

Previous studies showed that top-quality embryo transfer (ET), number of transferred embryos, endometrial preparation with natural cycles or mild stimulation, and female BMI independently affected the outcome in frozen-thawed ET. However, the effect of culturing thawed cleavage embryos to blastocyst stage on the outcome was not sufficiently elucidated. Our objective is to evaluate the role of this extended culturing as predictor of cycle outcome in vitrified-thawed ICSI cycles.

Materials and methods

One thousand forty-two consecutive cycles of vitrified-thawed ET done in a single IVF unit [Mansoura Integrated Fertility Centre (MIFC)] were reviewed during a period from 2014 to 2017. Endometrial preparation methods were natural, stimulation by antiestrogen and/or gonadotropins, or replacement using sequential estradiol (E2) and progesterone (P4). The primary outcome was the clinical pregnancy rate while the secondary outcome was the chemical and ongoing pregnancy rate.

Results

Overall clinical pregnancy rate (CPR) is 298/1042 is 28.5%, chemical pregnancy rate (326/1042) 31.3%, and ongoing pregnancy rate (167/615) 27.2%. Comparing clinically pregnant (n = 298) and non-pregnant (n = 744) showed, respectively, the following: age 28.76 ± 5.0, 28.85 ± 5.18 (p = 0.8); BMI 31.06 ± 5.9, 32.45 ± 5.9 (p = 0.002); infertility duration 4.17 ± 3.2, 4.6 ± 3.5 (p = 0.038); endometrial thickness 10.82 ± 1.6, 10.13 ± 2.06 (p = 0.0001); and no. of ET 3.35 ± 1.5, 3.12 ± 1.60 (p = 0.035). The clinical pregnancy rate when vitrification was done on cleavage embryos was 198/502 (39.4%), and when vitrification done on blastocyst stage 100/ 536 (18.7%) (P < 0.0001); endometrial preparation: natural 72/240(29.1%), stimulated 204/680 (30.0%) replacement 17/90 (18.8%) (p = 0.09); extended culture of cleavage embryos to blastocyst stage: clinical pregnancy rate 116/194 (59.7%) chemical pregnancy rate 125/194 (64.1%), ongoing pregnancy rate 87/165 (52.7%) and non extended culture clinical pregnancy rate 182/848 (21.4%), chemical pregnancy rate 201/848 (23.7%), and ongoing pregnancy rate 80/450 (17.7%) (P < 0.0001).

Conclusion

Top-quality ET, number of transferred embryos and extended culture of cleavage embryos to blastocyst stage, cleavage embryos but not infertility duration, BMI, endometrial thickness, or hCG trigger of ovulation independently predict successful outcome in frozen cycle ET and extended culture of cleavage embryos significantly improved clinical and chemical and ongoing pregnancy rates.

Are Clinical Outcomes of Micro-TESE in Non-obstructive Azoospermic Men Affected by the Use of Fresh or Frozen Gametes?

Background: The combination of microsurgical testicular sperm extraction (mTESE) and intracytoplasmic sperm injection (ICSI) has become a common management option, with sperm motility being positively associated with successful outcomes. However, few studies have investigated whether the use of fresh or thawed gamete combinations affect clinical outcomes.

Objectives: To determine whether the clinical outcomes of ICSI cycles using mTESE recovered testicular sperm of non-obstructive azoospermia (NOA) patients are affected by using fresh or thawed gametes.

Material and Methods: A retrospective study was conducted of NOA patients who underwent mTESE between 2017 and 2020 at Monash IVF assisted reproductive clinics in Melbourne, Australia. The impact of gamete fresh/frozen status and sperm motility was investigated on clinical outcomes such as fertilization, blastocyst formation, clinical pregnancy, and live birth rates (LBRs).

Results:A total of 103 NOA patients underwent mTESE, with a 65.1% successful surgical-sperm-retrieval. In total 56 patients contributed to 68 ICSI cycles, with a 35.1% fertilization rate and 25% LBR per embryo transfer. Compared with fresh testicular sperm, thawed testicular sperm did not affect clinical outcomes, including LBRs [16.7% vs 12.0%; odds ratio (OR) 0.68 (0.18–2.70)]. However, the use of thawed oocytes had a negative effect on fertilization rates [fresh-oocytes, 37.8%; vitrified-oocytes, 34.5%; OR 0.86 (0.02–0.48)]. Cycles using only motile sperm had a greater fertilization rate than those using a combination of motile and non-motile sperm (49.6% vs 37.2%, p ¡ 0.05). Importantly, when exclusively non-motile sperm were available (n = 26 cycles) their injection resulted in a very low fertilization rate (2.7%) and no live births were recorded.

Conclusion: Micro-TESE is an effective treatment for NOA patients, with no clear advantage of using fresh over thawed sperm, however, the use of vitrified compared with fresh oocytes requires further investigation. Importantly, patients should be informed of the poor outcomes with the use of non-motile sperm in mTESE ICSI cycles.

The use of fresh compared to frozen ejaculated sperm has no impact on fresh embryo transfer cycle reproductive outcomes

PURPOSE

To compare the reproductive outcomes of fresh embryo transfer (ET) cycles utilizing fresh versus frozen ejaculated sperm.

METHODS

First autologous fresh embryo transfer cycles at a single high-volume academic institution between 2013 and 2019 were retrospectively reviewed. IVF cycles using ejaculated sperm were included, and cycles using donor or surgically retrieved sperm were excluded. Sperm concentration was stratified as ≥ 5 and < 5 million/ml. The primary outcome was live birth, and the secondary outcomes were clinical intrauterine pregnancy (IUP) and miscarriage. A multivariable logistic regression model for the aforementioned outcomes was adjusted a priori for sperm concentration as well as maternal and paternal age.

RESULTS

A total of 6128 couples were included. Of these, 5780 (94.3%) utilized fresh sperm, and 348 (5.7%) frozen sperm. A total of 5716 (93.2%) had sperm concentrations ≥ 5 million/ml and 412 (6.7%) had sperm concentrations < 5 million/ml. On multivariable logistic regression, the use of freshly ejaculated sperm was not associated with significantly different odds of clinical IUP, miscarriage, or live birth when compared to cycles using frozen sperm.

CONCLUSION

For couples conceiving via fresh ET, the use of fresh versus frozen ejaculated sperm is not associated with reproductive outcomes.

Management of male factor infertility: position statement from the Italian Society of Andrology and Sexual Medicine (SIAMS) : Endorsing Organization: Italian Society of Embryology, Reproduction, and Research (SIERR)

PURPOSE

Infertility affects 15-20% of couples and male factors are present in about half of the cases. For many aspects related to the diagnostic and therapeutic approach of male factor infertility, there is no general consensus, and the clinical approach is not uniform.

METHODS

In the present document by the Italian Society of Andrology and Sexual Medicine (SIAMS), endorsed by the Italian Society of Embryology, Reproduction, and Research (SIERR), we propose evidence-based recommendations for the diagnosis, treatment, and management of male factor infertility to improve patient and couple care.

RESULTS

Components of the initial evaluation should include at minimum medical history, physical examination, and semen analysis. Semen microbiological examination, endocrine assessment, and imaging are suggested in most men and recommended when specific risk factors for infertility exist or first-step analyses showed abnormalities. Full examination including genetic tests, testicular cytology/histology, or additional tests on sperm is clinically oriented and based on the results of previous investigations. For treatment purposes, the identification of the specific cause and the pathogenetic mechanism is advisable. At least, distinguishing pre-testicular, testicular, and post-testicular forms is essential. Treatment should be couple-oriented, including lifestyle modifications, etiologic therapies, empirical treatments, and ART on the basis of best evidence and with a gradual approach.

CONCLUSION

These Guidelines are based on two principal aspects: they are couple-oriented and place high value in assessing, preventing, and treating risk factors for infertility. These Guidelines also highlighted that male infertility and in particular testicular function might be a mirror of general health of a man.

Effect of Sperm Cryopreservation on miRNA Expression and Early Embryonic Development

Although sperm preservation is a common means of personal fertility preservation, its effects on embryonic development potential need further investigation. The purpose of this study was to identify key microRNA (miRNA) in cryopreserved sperm and determine the changes of these miRNAs and their target genes during embryonic development using cryopreserved sperm. Moreover, the embryonic development potential of cryopreserved sperm was estimated in assisted reproductive technology (ART), where key miRNAs and target genes were validated in sperm and subsequent embryos. Clinical data of embryonic development from cryopreserved sperm indicated a significant decrease in fertilization rate in both in vitro fertilization (IVF) and intracytoplasmic sperm injection (ICSI) cases, as well as a reduction in blastocyst formation rate in ICSI cases. Meanwhile there was a significant increase in blocked embryo ratio of Day1, Day2, and Day3.5 embryos when frozen-thawed mouse sperm was used, compared with fresh mouse sperm, suggesting a potential negative effect of sperm cryopreservation on embryonic development. From frozen-thawed and fresh sperm in humans and mice, respectively, 21 and 95 differentially expressed miRNAs (DEmiRs) were detected. miR-148b-3p were downregulated in both human and mouse frozen-thawed sperm and were also decreased in embryos after fertilization using cryopreserved sperm. Target genes of miR-148b-3p, Pten, was identified in mouse embryos using quantitative real-time PCR (qRT-PCR) and Western blot (WB). In addition, common characters of cryopreservation of mouse oocytes compared with sperm were also detected; downregulation of miR-148b-3p was also confirmed in cryopreserved oocytes. In summary, our study suggested that cryopreservation of sperm could change the expression of miRNAs, especially the miR-148b-3p across humans and mice, and may further affect fertilization and embryo development by increasing the expression of Pten. Moreover, downregulation of miR-148b-3p induced by cryopreservation was conserved in mouse gametes.

Clinical Outcomes and Live Birth Rate Resulted From Microdissection Testicular Sperm Extraction With ICSI-IVF in Non-Obstructive Azoospermia: A Single-Center Cohort Study

BACKGROUND

Most of data available in the literature reported the sperm retrieval rate and limited intracytoplasmic sperm injection (ICSI) results of microdissection testicular sperm extraction (micro-TESE) in non-obstructive azoospermia (NOA) patients with different etiologies. Unfortunately, there is currently a lack of comprehensive data to guide clinicians in conducting comprehensive consultations with NOA patients.

OBJECTIVES

To obtain more comprehensive evidence-based data and clinical outcomes for better consultation of NOA patients who opted to undergo micro-TESE combined with ICSI-IVF.

METHODS

It was a retrospective study involved 968 NOA patients underwent micro-TESE during January 2015 to December 2019. Embryological, clinical, and live birth outcomes were demonstrated comprehensively and three kinds of stratification analyses were performed based on ICSI-IVF cycles using frozen and fresh sperm, different etiologies of NOA and various amounts of sperm retrieved.

RESULTS

The sperm retrieval rate was 44.6%, and ICSI was performed in 299 couples leading to 150 clinical pregnancies and 140 live-birth deliveries. The clinical pregnancy rate (CPR) was 50.17%, and the cumulative live birth rate (LBR) was 46.82%, and the low birth defects rate was 1.43%. No significant difference was observed about cumulative LBR in frozen sperm group and fresh sperm group (47.5% vs 42.9%, P>0.05). NOA patients with AZFc microdeletions had the lowest rate of a high-score embryo on day 3 (4.4%, P<0.05) and the lowest cumulative LBR (19.4%, P<0.05). NOA patients with lower sperm count (having fewer than 20 sperms retrieved) had significantly lower cumulative LBR than those with higher sperm count (having more than 20 sperms retrieved) (28.1% vs 51.9%, P<0.05).

CONCLUSIONS

For those NOA patients who stepped in ICSI-IVF cycles, the cumulative LBR was 46.82%. No significant difference was indicated in the LBR between ICSI-IVF cycles using frozen or fresh testicular sperm. Compared to other etiologies, NOA caused by AZFc microdeletions have the poorest embryological and clinical outcomes. Patients with less testicular sperm retrieved have poorer embryological and clinical outcomes.

Outcomes and affecting factors for ICSI and microTESE treatments in nonobstructive azoospermia patients with different etiologies: A retrospective analysis

INTRODUCTION

Nonobstructive azoospermia (NOA) is a common and severe form of male infertility. Microdissection testicular sperm extraction (microTESE) combined with intracytoplasmic sperm injection (ICSI) is an optimal treatment for men with NOA. However, the outcomes and affecting factors of ICSI for NOA patients with different etiologies receiving microTESE treatment are still unclear.

METHODS

A total of 335 NOA patients undergoing microTESE from January 2017 to December 2021 were included in this retrospective analysis. The patients were divided into five groups (idiopathic, Klinefelter syndrome (KS), Y chromosome microdeletions (YCMDs), cryptorchidism and mumps orchitis) according to the etiologies. The clinical characteristics and outcomes of microTESE and ICSI were collected and comparisons were performed between clinical characteristics of patients who had successful sperm retrieval (SSR) and sperm retrieval failure (SRF). In addition, relationships between clinical characteristics and rates of SSR were explored by Kendall correlation analysis.

RESULTS

The overall SSR rate was 40.90%. SSR rate of the idiopathic group (31.22%) was the lowest and was much lower than that of other groups (KS: 48.65%, 28/58; YCMDs: 60.87%; cryptorchidism: 80.95%; mumps orchitis: 75.00%). The overall fertilization rate was 72.26%. No group differences were found among five groups (idiopathic: 73.91%; KS: 71.43%; YCMDs: 64.29%; cryptorchidism: 70.59%; mumps orchitis: 77.78%). The overall clinical pregnancy rate was 66.67%. No group differences were found among five groups (idiopathic: 68.63%; KS: 65.00%; YCMDs: 44.44%; cryptorchidism: 66.67%; mumps orchitis: 85.71%). The overall live birth rate was 66.67%. No group differences were found among five groups (idiopathic: 71.43%; KS: 53.85%; YCMDs: 50.00%; cryptorchidism: 75.00%; mumps orchitis: 66.67%). For SSR patients, the average age was significantly lower in the idiopathic group, while the average testicular volume was significantly greater in the cryptorchidism and mumps orchitis groups. However, no significant differences were found in the level of follicle stimulating hormone (FSH), luteinizing hormone (LH) and testosterone (T) between patients who had SSR and SRF. In addition, negative relationships were found between age and rates of SSR in idiopathic NOA patients while positive relationships were found between testis volume and rates of SSR in patients with cryptorchidism and mumps orchitis.

CONCLUSION

Patients with idiopathic NOA had lowest SSR. In addition, the age in idiopathic NOA patients was a predictor for SSR while testicular volume in NOA patients with cryptorchidism and mumps orchitis was a predictor for SSR. However, the relationships between clinical characteristics and clinical outcomes in NOA patients were preliminary, and further validation needed to be carried out in a larger sample to increase statistical capacity before a definitive conclusion could be drawn.

All you need to know about sperm RNAs

BACKGROUND

Spermatogenesis generates a small and highly specialised type of cell that is apparently incapable of transcription and translation. For many years, this dogma was supported by the assumption that (i) the compact sperm nucleus, resulting from the substitution of histones by protamine during spermatogenesis, renders the genome inaccessible to the transcriptional machinery; and (ii) the loss of most organelles, including endoplasmic reticulum and ribosomes, limits or prevents translational activity. Despite these observations, several types of coding and non-coding RNAs have been identified in human sperm. Their functional roles, particularly during fertilisation and embryonic development, are only now becoming apparent.

OBJECTIVE AND RATIONALE

This review aimed to summarise current knowledge of the origin, types and functional roles of sperm RNAs, and to evaluate the clinical benefits of employing these transcripts as biomarkers of male fertility and reproductive outcomes. The possible contribution of sperm RNAs to intergenerational or transgenerational phenotypic inheritance is also addressed.

SEARCH METHODS

A comprehensive literature search on PubMed was conducted using the search terms 'sperm' AND 'RNA'. Searches focussed upon articles written in English and published prior to August 2020.

OUTCOMES

The development of more sensitive and accurate RNA technologies, including RNA sequencing, has enabled the identification and characterisation of numerous transcripts in human sperm. Though a majority of these RNAs likely arise during spermatogenesis, other data support an epididymal origin of RNA transmitted to maturing sperm by extracellular vesicles. A minority may also be synthesised by de novo transcription in mature sperm, since a small portion of the sperm genome remains packed by histones. This complex RNA population has important roles in paternal chromatin packaging, sperm maturation and capacitation, fertilisation, early embryogenesis and developmental maintenance. In recent years, additional lines of evidence from animal models support a role for sperm RNAs in intergenerational or transgenerational inheritance, modulating both the genotype and phenotype of progeny. Importantly, several reports indicate that the sperm RNA content of fertile and infertile men differs considerably and is strongly modulated by the environment, lifestyle and pathological states.

WIDER IMPLICATIONS

Transcriptional profiling has considerable potential for the discovery of fertility biomarkers. Understanding the role of sperm transcripts and comparing the sperm RNA fingerprint of fertile and infertile men could help to elucidate the regulatory pathways contributing to male factor infertility. Such data might also provide a molecular explanation for several causes of idiopathic male fertility. Ultimately, transcriptional profiling may be employed to optimise ART procedures and overcome some of the underlying causes of male infertility, ensuring the birth of healthy children.

Comparison of fresh and frozen ejaculated spermatozoa in sibling oocyte recipient cycles

RESEARCH QUESTION

Do IVF and intracytoplasmic sperm injection cycles using fresh and frozen ejaculated spermatozoa result in similar pregnancy outcomes in couples with non-male factor infertility?

DESIGN

Retrospective cohort study; patients undergoing donor egg recipient cycles, in which oocytes from a single ovarian stimulation were split between two recipients, were reviewed. Two recipients of oocytes from a single donor were paired and categorized based on the type of ejaculated spermatozoa (fresh/frozen). Outcomes included delivery rate, implantation, pregnancy, pregnancy loss and fertilization rates.

RESULTS

Of the 408 patients who received oocytes from a split donor oocyte cycle, 45 pairs of patients used discrepant types of ejaculated spermatozoa and were included in the study. Fertilization rate: fresh (74.8%); frozen (68.6%) (P = 0.13). Pregnancy rate: fresh (76%); frozen (67%); delivery rate: fresh (69%); frozen (44%); implantation rate was significantly higher: fresh (64%); frozen (36%) (P = 0.04). Rate of pregnancy loss was significantly higher in the frozen group compared with the fresh group (33% versus 5.9%, P = 0.013). Adjusted odds for delivery was 67% lower in the frozen group (95% CI 0.12, 0.89). Adjusted odds of pregnancy (adjusted OR 0.67, 95% CI 0.20, 2.27) and implantation (adjusted OR 0.5, 95% CI 0.12, 2.12) were not significantly different between the frozen and fresh sperm groups.

CONCLUSION

In this model that controls for oocyte quality by using paired recipients from the same donor, frozen ejaculated spermatozoa resulted in lower delivery rates than those using fresh spermatozoa.

Fresh vs frozen testicular sperm for assisted reproductive technology in patients with non-obstructive azoospermia: A systematic review

Objective

: To review the debate about the routine use of cryopreserved testicular sperm for intracytoplasmic sperm injection (ICSI) from patients with non-obstructive azoospermia (NOA), as some authors suggest repeating sperm retrieval in such cases due to poorer ICSI results when frozen–thawed testicular sperm is used compared with fresh sperm.

Methods

: A systematic literature review was performed in August 2020 using the Medical Literature Analysis and Retrieval System Online (MEDLINE), Web of Science databases and the Excerpta Medica dataBASE (EMBASE), and we included 26 studies that were considered eligible for this systematic review.

Results

: In all, 1189 publications were screened and 26 articles were included in the systematic review. Three meta-analysis reviews were included and they all concluded that the use of fresh and frozen sperms for ICSI from patients with NOA showed comparable fertilisation and pregnancy rates.

Conclusion

: The use of frozen testicular sperm from men with NOA results in fertilisation and clinical pregnancy rates similar to those of fresh sperm. This may encourage fertility centres to use frozen testicular sperm samples, as this policy has certain advantages that would help with organising their workflow.

Abbreviations: CPR: clinical pregnancy rate; 2PN%: two pronuclei % fertilisation rate; ICSI: intracytoplasmic sperm injection; NOA: non-obstructive azoospermia; OA, obstructive azoospermia; SCO: Sertoli cell-only syndrome; (micro-)TESE: (microsurgical) testicular sperm extraction

Microdissection testicular sperm extraction (micro-TESE) in men with infertility due to nonobstructive azoospermia: summary of current literature

PURPOSE

Nonobstructive azoospermia (NOA) is associated with intrinsic testicular defects that severely impair sperm production. Although NOA invariably leads to infertility, focal sperm production may exist in the testicles of affected patients, which can be retrieved and used for intracytoplasmic sperm injection (ICSI) to generate healthy offspring. However, geographic locations of testicular sperm producing-areas are uncertain, making microsurgical-guided sperm retrieval (microdissection testicular sperm extraction; micro-TESE) an attractive method to identify and retrieve sperm in patients with NOA due to spermatogenic failure. Given the widespread use of micro-TESE, its effectiveness in harvesting sperm and related potential complications need to be clarified.

METHODS

We queried PubMed/MEDLINE for studies published in English, from inception to May 2021, concerning the effect of micro-TESE on sperm retrieval rate (SRR), complication rate and ICSI pregnancy rate-using retrieved testicular sperm in subfertile couples where the male had NOA.

RESULTS

We found 116 articles, including 70 original papers, 32 review articles, and 14 systematic reviews. The evidence accounted for 4895 patients. Micro-TESE retrieved sperm in 46.6% of men with NOA, but SRRs varied considerably (18.4-70.8%) and were mainly related to the treated population characteristics. Concerning the general population of NOA patients who have not undergone previous sperm retrieval (naïve population), the SRR by micro-TESE was 46.8% (1833 of 3914 patients; range 20-70.8%; 28 studies). In studies reporting SR by micro-TESE for men who had failed percutaneous testicular sperm aspiration or non-microsurgical testicular sperm extraction, the SRR was 39.1% (127 of 325 patients; range 18.4-57.1%; 4 studies). Data on adverse events indicated that micro-TESE was associated with low (~ 3%) short-term postoperative complication rates. The fertilizing ability of testicular sperm retrieved by micro-TESE and used for ICSI was adequate (~ 57%), whereas clinical pregnancy and live birth were obtained in 39% and 24% of couples who had an embryo transfer, respectively. The health of the resulting children seems reassuring, but the evidence is limited. The procedure increases sperm retrieval success compared to non-microsurgical retrieval methods, particularly in men with Sertoli cell-only testicular histopathology.

CONCLUSION

We concluded that micro-TESE is an effective and safe method to retrieve sperm from men with NOA-related infertility, with potential advantages over non-microsurgical methods. Nevertheless, high-quality, head-to-head comparative randomized controlled trials by sperm retrieval method, focusing on SRR, live birth rate and assessing long-term adverse events and health of children conceived using testicular sperm from NOA patients are lacking. Therefore, further research is required to determine the full clinical implications of micro-TESE in male infertility treatment.

A cryoprotectant supplemented with pentoxifylline can improve the effect of freezing on the motility of human testicular sperm

This study examined the effect of a cryoprotectant with and without pentoxifylline supplementation on the motility and viability of human testicular sperm, both before and after freezing. Testicular samples were obtained from 68 patients with azoospermia who came to the Andrology Service of West China Second University Hospital, Sichuan University, for testicular biopsies from December 2019 to April 2020. All patients were assigned randomly to two groups: experimental, whose testicular sperm were added to the cryoprotectant with pentoxifylline, and the control, whose testicular sperm were added to the cryoprotectant without pentoxifylline. Both groups used the same freezing and thawing methods. Testicular sperm motility in the experimental group was significantly higher than that of the control group, both before and after cryopreservation. The recovery rate of sperm motility in the experimental group was significantly higher than that of the control group. The percentage of samples with motile testicular sperm in the experimental group was significantly higher than that of the control group after thawing. Sperm viability was unchanged between the experimental and control groups, both before and after freezing. Overall, a pentoxifylline-supplemented cryoprotectant can significantly improve the motility of testicular sperm before and after cryopreservation.

Sperm Selection Procedures for Optimizing the Outcome of ICSI in Patients with NOA

Retrieving spermatozoa from the testicles has been a great hope for patients with non-obstructive azoospermia (NOA), but relevant methods have not yet been developed to the level necessary to provide resolutions for all cases of NOA. Although performing testicular sperm extraction under microscopic magnification has increased sperm retrieval rates, in vitro selection and processing of quality sperm plays an essential role in the success of in vitro fertilization. Moreover, sperm cryopreservation is widely used in assisted reproductive technologies, whether for therapeutic purposes or for future fertility preservation. In recent years, there have been new developments using advanced technologies to freeze and preserve even very small numbers of sperm for which conventional techniques are inadequate. The present review provides an up-to-date summary of current strategies for maximizing sperm recovery from surgically obtained testicular samples and, as an extension, optimization of in vitro sperm processing techniques in the management of NOA.

Time-lapse imaging of human embryos fertilized with testicular sperm reveals an impact on the first embryonic cell cycle

Testicular sperm is increasingly used during in vitro fertilization treatment. Testicular sperm has the ability to fertilize the oocyte after intracytoplasmic sperm injection (ICSI), but they have not undergone maturation during epididymal transport. Testicular sperm differs from ejaculated sperm in terms of chromatin maturity, incidence of DNA damage, and RNA content. It is not fully understood what the biological impact is of using testicular sperm, on fertilization, preimplantation embryo development, and postimplantation development. Our goal was to investigate differences in human preimplantation embryo development after ICSI using testicular sperm (TESE-ICSI) and ejaculated sperm. We used time-lapse embryo culture to study these possible differences. Embryos (n = 639) originating from 208 couples undergoing TESE-ICSI treatment were studied and compared to embryos (n = 866) originating from 243 couples undergoing ICSI treatment with ejaculated sperm. Using statistical analysis with linear mixed models, we observed that pronuclei appeared 0.55 h earlier in TESE-ICSI embryos, after which the pronuclear stage lasted 0.55 h longer. Also, significantly more TESE-ICSI embryos showed direct unequal cleavage from the 1-cell stage to the 3-cell stage. TESE-ICSI embryos proceeded faster through the cleavage divisions to the 5- and the 6-cell stage, but this effect disappeared when we adjusted our model for maternal factors. In conclusion, sperm origin affects embryo development during the first embryonic cell cycle, but not developmental kinetics to the 8-cell stage. Our results provide insight into the biological differences between testicular and ejaculated sperm and their impact during human fertilization.

The evolution of testicular sperm extraction and preservation techniques

Along with the advent of intracytoplasmic sperm injection in 1992, sperm retrieval procedures now allow the possibility of conception from male sterility. In cases of sterility due to blockages in the reproductive tract, sperm retrieval procedures are relatively straightforward and reliable. In nonobstructive azoospermia or testis failure, sperm often can be difficult to retrieve. For this reason, the field of testicular sperm retrieval has witnessed tremendous change and innovation to achieve higher sperm yields, increasing efficiency and safety, along with fewer complications. We review the history and evolution of testicular sperm retrieval since its inception. Using the findings from randomized controlled trials, basic science studies, meta-analyses, case-controlled or cohort studies, best-practice policies, and literature reviews, we outline the concepts, facts, and principles that have been elucidated over several decades of experience with sperm retrieval. We also appraise the merits and issues of the most popular sperm retrieval techniques and strategies. Finally, we define areas of future clinical and laboratory development that will further refine the field of testicular sperm retrieval.

Testicular sperm retrieval: What should we expect from the fresh and subsequent cryopreserved sperm injection?

We sought to compare ICSI outcomes of cycle using fresh versus thawed TESE spermatozoa obtained during the previous fresh TESE. All consecutive couples undergoing ICSI cycles using fresh TESE spermatozoa, followed by ICSI cycle using cryopreserved sperm remaining from the previous fresh TESE procedure were included. Ovarian stimulation (OS)/laboratory variables and cycle outcome were assessed and compared between those utilising fresh versus thawed TESE spermatozoa. Seventy-five couples were evaluated, with no in-between groups differences in OS nor embryological variables. While implantation and LBR per embryo transfer were nonsignificantly higher in the frozen as compared to the fresh TESE, there was a trend towards higher LBRs per patient in the frozen TESE group. The cumulative miscarriage rate (4% versus 14.7%, p < .022 respectively) was significantly lower and the cumulative LBR (34.7% versus 16%, p < .007 respectively) was significantly higher using frozen TESE spermatozoa. Moreover, significantly higher proportion of frozen TESE sperm samples used pentoxifylline to enhance sperm motility. In conclusion, the results of ICSI cycles using frozen TESE spermatozoa are as good, or even better than using fresh TESE spermatozoa. Further studies are required to explore the factors responsible for the improved ICSI outcome, while using frozen versus fresh TESE sperm samples.

Impact on using cryopreservation of testicular or epididymal sperm upon intracytoplasmic sperm injection outcome in men with obstructive azoospermia: a systematic review and meta-analysis

PURPOSE

To determine whether there was a significant impact on using cryopreservation of testicular or epididymal sperm upon the outcomes of intracytoplasmic sperm injection (ICSI) in patients with obstructive azoospermia (OA).

METHOD

Systematic review and meta-analysis of 20 retrospective studies in databases from January 1, 1995, to June 1, 2020.

RESULT

Twenty articles were included in this study. A total of 3602 (64.1%) of 5616 oocytes injected with fresh epididymal sperm were fertilized, compared with 2366 (61.2%) of 3862 oocytes injected with cryopreserved sperm (relative risk ratio (RR) 0.96, 95% confidence interval (CI) (0.90, 1.02), P > 0.05). A total of 303 (44.1%) of 687 ICSI cycles using fresh epididymal sperm resulted in a clinical pregnancy, compared with 150 (36.6%) of 410 ICSI cycles using cryopreserved epididymal sperm (RR 0.84, 95% CI (0.72, 0.97), P < 0.05). In the testis, a total of 2147 (68.7%) of 3125 oocytes injected with fresh sperm were fertilized, compared with 1623 (63.5%) of 2557 oocytes injected with cryopreserved sperm (RR 0.97, 95% CI (0.90, 1.06), P > 0.05). A total of 151 (47.8%) of 316 ICSI cycles using fresh testicular sperm resulted in a clinical pregnancy, compared with 113 (38.2%) of 296 ICSI cycles using cryopreserved sperm (RR 0.87, 95% CI (0.72, 1.05), P > 0.05).

CONCLUSIONS

In men with OA, there was a statistical lower clinical pregnancy rate (CPR) by using frozen epididymal sperm compared with fresh epididymal sperm, but showing no difference on fertilization rate (FR). Additionally, FR and CPR were not affected by whether the retrieved testicular sperm was frozen or fresh.

Intracytoplasmic sperm injection with fresh versus cryopreserved testicular sperm in azoospermic patients

Background

The purpose of this study is to compare the outcome of intracytoplasmic sperm injection (ICSI) using fresh sperm versus frozen-thawed sperm in both obstructed and non-obstructed azoospermias. This retrospective study included 159 ICSI cycles from 126 couples. In 91 obstructed azoospermia cases, 66 cycles were treated with fresh testicular sperm and 25 cycles were treated with frozen-thawed testicular samples. In 68 non-obstructed azoospermia cases, 32 cycles were treated with fresh testicular sperm and 36 cycles were treated with frozen-thawed testicular sperm, and the main measure and outcomes calculated are fertilization rate, clinical pregnancy, and live birth rate.

Results

In case of obstructed azoospermia, there were no statistically significant differences between fresh sperm and frozen-thawed testicular sperm used for ICSI regarding fertilization rate, clinical pregnancy rate, and live birth rate as shown (57%, 47%, 0.093 p value; 23.7%, 17.4%, 0.54 p value; and 11.9%, 8.7%, 0.68 p value, respectively). Non-obstructed azoospermia cases also show no significant differences in fertilization rate (37%, 36%, 0.91 p value), clinical pregnancy rate (20%, 14.3%, 0.58 p value), and live birth rate (4%, 3.6%, 0.93 p value).

Conclusion

Cryopreservation of testicular sperm is reliable if carried out before ovulation induction especially in cases with non-obstructive azoospermia

Comparison and outcomes of nonobstructive azoospermia patients with different etiology undergoing MicroTESE and ICSI treatments

Background

The purpose of the study was to compare clinical, laboratory, histological features, microdissection testicular sperm extraction (MicroTESE) and intracytoplasmic sperm injection (ICSI) treatment outcomes of nonobstructive azoospermia (NOA) patients of various etiologies, and to investigate ICSI outcomes using fresh and frozen thawed sperms from MicroTESE, so to explore an optimal MicroTESE-ICSI procedure for NOA couples.

Methods

A retrospective analysis was made in 595 NOA patients undergoing MicroTESE from January 2013 to December 2017. The men were classified into six groups based on etiology. Patients' age, history, hormone profile, testis volume, testicular histology, sperm retrieval, fertile and pregnancy outcomes of ICSI were included for analysis.

Results

A total of 595 NOA patients were included in this study, with 446 (75.0%) were idiopathic NOA, 66 (11.1%) were Klinefelter syndrome (KS), 34 (5.7%) with microdeletion of the AZFc, 33 (5.5%) cases had the history of cryptorchidism, 13 (2.2%) had a history of mumps orchitis, and 3 (0.5%) cases underwent chemotherapy. The overall sperm retrieval rate (SRR) was 40.3% (240/595), SRR of the cryptorchidism (84.8%, 28/33) and mumps orchitis (84.6%, 11/13) groups were much higher than that of other groups, the SRR of idiopathic group was the lowest (31.8%, 142/446). One hundred and ninety-eight ICSI cycles utilizing MicroTESE sperm were retrospectively analyzed, including 155 fresh MicroTESE ICSI cycles and 43 frozen-thawed MicroTESE ICSI cycles. Fertilization rate, cleavage rate, and clinical pregnancy rate of fresh sperm group were slightly higher than those in frozen thawed MicroTESE sperm group, but high qualified embryo rate of fresh sperm group was lower than frozen thawed group. The differences were of no statistical meaning.

Conclusions

Etiology may be an effective prognostic factor for SRR in NOA patients. NOA of definite etiology, such as cryptorchidism, has high SRR, while idiopathic NOA, the most common type of NOA, has the lowest SRR. Using of frozen thawed sperm from MicroTESE had similar pregnant outcome to that of fresh sperm, so cryopreservation of testicular sperm seems to be more suitable and of great benefit in these cases and good results can also be expected when oocyte retrieval and ICSI are not performed at the same time.