Towards a better testicular sperm extraction: novel sperm sorting technologies for non-motile sperm extracted by microdissection TESE

Evaluation of an artificial intelligence-facilitated sperm detection tool in azoospermic samples for use in ICSI

RESEARCH QUESTION

Can artificial intelligence (AI) improve the efficiency and efficacy of sperm searches in azoospermic samples?

DESIGN

This two-phase proof-of-concept study began with a training phase using eight azoospermic patients (>10,000 sperm images) to provide a variety of surgically collected samples for sperm morphology and debris variation to train a convolutional neural network to identify spermatozoa. Second, side-by-side testing was undertaken on two cohorts of non-obstructive azoospermia patient samples: an embryologist versus the AI identifying all the spermatozoa in the still images (cohort 1, n = 4), and a side-by-side test with a simulated clinical deployment of the AI model with an intracytoplasmic sperm injection microscope and the embryologist performing a search with and without the aid of the AI (cohort 2, n = 4).

RESULTS

In cohort 1, the AI model showed an improvement in the time taken to identify all the spermatozoa per field of view (0.02 ± 0.30  ×  10-5s versus 36.10 ± 1.18s, P < 0.0001) and improved recall (91.95 ± 0.81% versus 86.52 ± 1.34%, P < 0.001) compared with an embryologist. From a total of 2660 spermatozoa to find in all the samples combined, 1937 were found by an embryologist and 1997 were found by the AI in less than 1000th of the time. In cohort 2, the AI-aided embryologist took significantly less time per droplet (98.90 ± 3.19 s versus 168.7 ± 7.84 s, P < 0.0001) and found 1396 spermatozoa, while 1274 were found without AI, although no significant difference was observed.

CONCLUSIONS

AI-powered image analysis has the potential for seamless integration into laboratory workflows, to reduce the time to identify and isolate spermatozoa from surgical sperm samples from hours to minutes, thus increasing success rates from these treatments.

Male Infertility: New Developments, Current Challenges, and Future Directions

There have been many significant scientific advances in the diagnostics and treatment modalities in the field of male infertility in recent decades. Examples of these include assisted reproductive technologies, sperm selection techniques for intracytoplasmic sperm injection, surgical procedures for sperm retrieval, and novel tests of sperm function. However, there is certainly a need for new developments in this field. In this review, we discuss advances in the management of male infertility, such as seminal oxidative stress testing, sperm DNA fragmentation testing, genetic and epigenetic tests, genetic manipulations, artificial intelligence, personalized medicine, and telemedicine. The role of the reproductive urologist will continue to expand in future years to address different topzics related to diverse questions and controversies of pathophysiology, diagnosis, and therapy of male infertility, training researchers and physicians in medical and scientific research in reproductive urology/andrology, and further development of andrology as an independent specialty.

MACS-DGC sperm preparation method resulted in high-quality sperm, top-quality embryo, and higher blastocyst rate in male factor infertile couples with high DNA fragmented sperm

Conventional sperm selection based on motility and morphology fails to provide detailed information on sperm functional and molecular status. Magnetic-activated cell sorting (MACS) protocol aims to optimize this process by selecting apoptotic sperm cells. Phospholipase C zeta-1 (PLCz1) is a physiological stimulus for oocyte activation and early embryonic development. The purpose of this study was to examine seminal parameters, DNA fragmentation index (DFI), and PLCz1 expression levels in MACS-DGC sorted specimens (DFI > 30%) and assess early development in resulting embryos. Semen specimens from 60 patients diagnosed with male factor infertility were collected and processed by either density gradient centrifugation (DGC) or MACS-DGC protocols. Pre and post-preparation analysis was performed. PLCz1 expression was assessed using the RT-PCR method. Retrieved eggs from their partners were divided into two groups in which they were injected with different sorted sperm. The fertilization rate and embryonic development were evaluated. While sperm's progressive motility and morphology significantly improved, there was a substantial decline in DFI following MACS-DGC. Fertilization rates were almost the same between the groups, and the latter resulted in remarkably more top-quality embryos and more blastocysts. PLCz1 expression was considerably higher in the MACS-DGC group. By eliminating apoptotic cells, the MACS-DGC technique could sort highly PLCz1-expressed sperm, optimize sperm selection in individuals with elevated DFI, development of resulting embryos.

Only the Best of the Bunch-Sperm Preparation Is Not Just about Numbers

In this Seminar, we present an overview of the current and emerging methods and technologies for optimizing the man and the sperm sample for fertility treatment. We argue that sperms are the secret to success, and that there are many avenues for improving both treatment and basic understanding of their role in outcomes. These outcomes encompass not just whether treatment is successful or not, but the wider intergenerational health of the offspring. We discuss outstanding challenges and opportunities of new technologies such as microfluidics and artificial intelligence, including potential pitfalls and advantages. This article aims to provide a comprehensive overview of the importance of sperm in fertility treatment and suggests future directions for research and innovation.

Staged Laboratory Processing of Testicular Tissue in Non-Obstructive Azoospermia May Rescue Retrieving an Existing Sperm: A Case Report and Literature Review

Non-obstructive azoospermia (NOA) is the most difficult form of male infertility to manage. It usually requires sperm retrieval from the testis, which is most challenging due to sperm rarity. Here, we describe the recovery of testicular sperms that had been missing and whose original retrieval results were negative. Salvage microsurgical testicular sperm extraction and sperm testing were performed on a 36-year-old male with NOA. Neither in the operation room nor after an inspection in the embryology laboratory were any sperm detected. The obtained tissue was advised to be frozen because the patient data and surgical microscopy predicted a favorable outcome, and the tissue processing was done in an inappropriate environment. About 1 month later, the specimen was thawed, crushed, and re-examined. Successful oocyte fertilization resulted from an effective detection of sperms and their direction to intra-cytoplasmic sperm injection. This is the first case report that, to the best of our knowledge, describes the stepwise laboratory processing of testicular tissue and its capacity to recover lost sperms in challenging NOA cases and under less-than-ideal working conditions.

Comparative Clinical Study of Percutaneous Epididymal Sperm Aspiration and Testicular Biopsy in the Outcome of ICSI-Assisted Fertility Treatment in Patients with Obstructive Azoospermia

Objective

To compare and contrast the effects of percutaneous epididymal sperm aspiration (PESA) and testicular sperm aspiration (TESA) on the outcome of intracytoplasmic sperm injection (ICSI)-assisted fertility treatment in patients with obstructive azoospermia.

Methods

Patients with obstructive azoospermia with an age distribution of 20–36 years admitted to the male department of the Reproductive Center of the Second Affiliated Hospital of South China University (Hengyang Nanhua Xing Hui Reproductive Health Hospital) from December 2018 to December 2020 were used in this study. One group was set up as the PESA group to perform PESA, and the other group was set up as the TESA group to perform percutaneous testicular biopsy for sperm extraction. Patients who were unsuccessful in PESA continued to undergo TESA, and if sperm were retrieved, they were classified as the TESA group. General information on male patients and their partners was collected and compared in patients from different sperm source groups. Embryo development (normal fertilization rate, high-quality embryo rate, and high-quality blastocyst rate) and pregnancy outcome (clinical pregnancy rate, miscarriage rate, and ectopic pregnancy rate) were compared between the two groups.

Results

Finally, there were 26 patients in the PESA group and 31 patients in the TESA group. There were no significant differences in terms of age, years of infertility, testosterone level, (FSH) follicle-stimulating hormone level, and testicular volume between the male patients in the PESA and TESA groups of two different sperm sources, and no significant differences were found in the general conditions of the female patients in terms of age, number of eggs obtained, number of sinus follicles, basal FSH value, and basal E2 value (p > 0.05). The rate of high-quality blastocysts in the TESA group was significantly higher than that in the PESA group (p < 0.05); the differences in clinical normal fertilization rate, high-quality embryo rate, clinical pregnancy rate, miscarriage rate, and ectopic pregnancy rate between the two groups were not statistically significant (p > 0.05).

Conclusion

ICSI with different sources of sperm in patients with male factor infertility alone, which had no significant effect on embryo development, embryo implantation rate, clinical pregnancy rate, and miscarriage rate, resulting in better clinical outcomes.

Electrically-driven handling of gametes and embryos: taking a step towards the future of ARTs

Electrical stimulation of gametes and embryos and on-chip manipulation of microdroplets of culture medium serve as promising tools for assisted reproductive technologies (ARTs). Thus far, dielectrophoresis (DEP), electrorotation (ER) and electrowetting on dielectric (EWOD) proved compatible with most laboratory procedures offered by ARTs. Positioning, entrapment and selection of reproductive cells can be achieved with DEP and ER, while EWOD provides the dynamic microenvironment of a developing embryo to better mimic the functions of the oviduct. Furthermore, these techniques are applicable for the assessment of the developmental competence of a mammalian embryo in vitro. Such research paves the way towards the amelioration and full automation of the assisted reproduction methods. This article aims to provide a summary on the recent developments regarding electrically stimulated lab-on-chip devices and their application for the manipulation of gametes and embryos in vitro.

The Future of IVF: The New Normal in Human Reproduction

Increased demand for in vitro fertilization (IVF) due to socio-demographic trends, and supply facilitated by new technologies, converged to transform the way a substantial proportion of humans reproduce. The purpose of this article is to describe the societal and demographic trends driving increased worldwide demand for IVF, as well as to provide an overview of emerging technologies that promise to greatly expand IVF utilization and lower its cost.

Cross flow coupled with inertial focusing for separation of human sperm cells from semen and simulated TESE samples

A triplet spiral channel coupled with cross-flow filtration has been designed and fabricated in an effort to separate sperm cells from either semen or simulated testicular sperm extraction (TESE) samples. This device separates a fraction of cells from the sample by taking advantage of inertial focusing combined with hydrodynamic filtration in multiple micro-slits. Compared to the conventional swim-up technique, the proposed microfluidic device is capable of efficiently separating sperm cells without any tedious semen sample processing and centrifugation steps with a lower level of reactive oxygen species and DNA fragmentation. The device processing capability on the simulated TESE samples confirmed its proficiency in retrieving sperm cells from the samples with an approximate yield of 76%. Conclusively, the introduced microfluidic device can pave the path to proficiently separate sperm cells in assisted reproductive treatment cycles.

Success rate and ART outcome of microsurgical sperm extraction in non obstructive azoospermia: A retrospective study

Background

The management of non-obstructive azoospermia (NOA) disease relies on microdissection testicular sperm extraction (micro-TESE). Few studies have assessed the role of micro-TESE in men with NOA in our country.

Objective

The aim of the current study was to investigate the success rate of micro-TESE.

Materials and Methods

This retrospective descriptive-analytical study was conducted on 463 men with NOA in Yazd Reproductive Sciences Institute during September 2017 through September 2019. Sperm were retrieved and frozen according to the rapid sperm freezing protocol. After preparing the oocyte of the male partner's spouse, sperms were thawed and then entered the intracytoplasmic sperm injection process. The clinical pregnancy of individuals was confirmed via ultrasound. Demographic data were extracted from medical records.

Results

The success rate of micro-TESE was 38% and successful fertilization, biochemical pregnancy, clinical pregnancy, and live birth were observed in 111 (85.4%), 29 (22.3%), 29 (22.3%) and 14 (10.7%) men, respectively. A significant difference was seen between the two groups, regarding age (p = 0.01). In addition, the mean follicle-stimulating hormone in men with positive micro-TESE was significantly lower than in men with negative micro-TESE (p = 0.02).

Conclusion

The success of pregnancy in couples with NOA managed via micro-TESE was significant. The study found that the success rate of micro-TESE was higher in older men and in those with lower follicle-stimulating hormone levels.

Microfluidic Systems for Isolation of Spermatozoa from Testicular Specimens of Non-Obstructive Azoospermic Men: Does/Can It Improve Sperm Yield?

Intracytoplasmic sperm injection (ICSI) has allowed reproduction options through assisted reproductive technologies (ARTs) for men with no spermatozoa within the ejaculate (azoospermia). In men with non-obstructive azoospermia (NOA), the options for spermatozoa retrieval are testicular sperm extraction (TESE), testicular sperm aspiration (TESA), or micro-surgical sperm extraction (microTESE). At the initial time of spermatozoa removal from the testis, spermatozoa are immobile. Independent of the means of spermatozoa retrieval, the subsequent steps of removing spermatozoa from seminiferous tubules, determining spermatozoa viability, identifying enough spermatozoa for oocyte injections, and isolating viable spermatozoa for injection are currently performed manually by laboratory microscopic dissection and collection. These laboratory techniques are highly labor-intensive, with yield unknown, have an unpredictable efficiency and/or success rate, and are subject to inter-laboratory personnel and intra-laboratory variability. Here, we consider the potential utility, benefits, and shortcomings of developing technologies such as motility induction/stimulants, microfluidics, dielectrophoresis, and cell sorting as andrological laboratory add-ons to reduce the technical burdens and variabilities in viable spermatozoa isolation from testicular samples in men with NOA.

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.

A microfluidic approach to rapid sperm recovery from heterogeneous cell suspensions

The isolation of sperm cells from background cell populations and debris is an essential step in all assisted reproductive technologies. Conventional techniques for sperm recovery from testicular sperm extractions stagnate at the sample processing stage, where it can take several hours to identify viable sperm from a background of collateral cells such as white bloods cells (WBCs), red blood cells (RBCs), epithelial cells (ECs) and in some cases cancer cells. Manual identification of sperm from contaminating cells and debris is a tedious and time-consuming operation that can be suitably addressed through inertial microfluidics. Microfluidics has proven an effective technology for high-quality sperm selection based on motility. However, motility-based selection methods cannot cater for viable, non-motile sperm often present in testicular or epididymal sperm extractions and aspirations. This study demonstrates the use of a 3D printed inertial microfluidic device for the separation of sperm cells from a mixed suspension of WBCs, RBCs, ECs, and leukemic cancer cells. This technology presents a 36-fold time improvement for the recovery of sperm cells (> 96%) by separating sperm, RBCS, WBCs, ECs and cancer cells into tight bands in less than 5 min. Furthermore, microfluidic processing of sperm has no impact on sperm parameters; vitality, motility, morphology, or DNA fragmentation of sperm. Applying inertial microfluidics for non-motile sperm recovery can greatly improve the current processing procedure of testicular sperm extractions, simplifying the fertility outcomes for severe forms of male infertility that warrant the surgery.