Sperm retrieval for azoospermia and intracytoplasmic sperm injection success rates--a personal overview

Microscopic Epididymal Sperm Aspiration (MESA) Should be Employed Over Testicular Sperm Extraction (TESE) Sperm Retrieval Surgery for Obstructive Azoospermia (OA)

INTRODUCTION

 Testicular sperm extraction (TESE) has been widely used as a sperm extraction surgery for azoospermia even for obstructive azoospermia (OA) because it does not require surgical skill. However, there are postoperative pain issues, and subsequent testicular atrophy and decreased testosterone levels may occur with TESE. This study examines the usefulness of microscopic epididymal sperm aspiration (MESA) for OA.

METHODS

 We studied 108 patients diagnosed with OA and treated with MESA at our institute between April 2004 and December 2021. The MESA was performed using a micropipette with a micropuncture technique under an operative microscope. When no sperm were present or motility was not observed, additional punctures to the epididymal tubule were performed.

RESULTS

 Motile sperm were recovered in all cases (108 cases). Of these, intracytoplasmic sperm injection (ICSI) using frozen-thawed sperm was performed in 101 cases and the normal fertilization rate was 76.2%. A total of 436 embryo transfer (ET) cycles were performed. The implantation rate per transfer cycle was 47.9%, the clinical pregnancy rate was 41.0%, and the live birth rate was 23.7%. The per-case live birth rate was 84.8%.

CONCLUSIONS

 MESA-ICSI has a very good fertilization rate, clinical pregnancy rate, and delivery rate. Furthermore, the patient's postoperative pain is less, the number of sperm collected is larger, the burden on the embryologist who processes the collected sperm is less, and ICSI can be easily attempted after frozen-thawed sperm. MESA rather than TESE should be employed for the OA subjects.

Differential responsiveness of spermatogonia to retinoic acid dictates precocious differentiation but not meiotic entry during steady-state spermatogenesis†

The foundation of mammalian spermatogenesis is provided by undifferentiated spermatogonia, which comprise of spermatogonial stem cells (SSCs) and transit-amplifying progenitors that differentiate in response to retinoic acid (RA) and are committed to enter meiosis. Our laboratory recently reported that the foundational populations of SSCs, undifferentiated progenitors, and differentiating spermatogonia are formed in the neonatal testis in part based on their differential responsiveness to RA. Here, we expand on those findings to define the extent to which RA responsiveness during steady-state spermatogenesis in the adult testis regulates the spermatogonial fate. Our results reveal that both progenitor and differentiating spermatogonia throughout the testis are capable of responding to exogenous RA, but their resulting fates were quite distinct-undifferentiated progenitors precociously differentiated and proceeded into meiosis on a normal timeline, while differentiating spermatogonia were unable to hasten their entry into meiosis. This reveals that the spermatogonia responding to RA must still complete the 8.6 day differentiation program prior to their entry into meiosis. Addition of exogenous RA enriched testes with preleptotene and pachytene spermatocytes one and two seminiferous cycles later, respectively, supporting recent clinical studies reporting increased sperm production and enhanced fertility in subfertile men on long-term RA analog treatment. Collectively, our results reveal that a well-buffered system exists within mammalian testes to regulate spermatogonial RA exposure, that exposed undifferentiated progenitors can precociously differentiate, but must complete a normal-length differentiation program prior to entering meiosis, and that daily RA treatments increased the numbers of advanced germ cells by directing undifferentiated progenitors to continuously differentiate.

Prediction model for live birth in ICSI using testicular extracted sperm

STUDY QUESTION

Which parameters have a predictive value for live birth in couples undergoing ICSI after successful testicular sperm extraction (TESE-ICSI)?

SUMMARY ANSWER

Female age, a first or subsequent started TESE-ICSI cycle, male LH, male testosterone, motility of the spermatozoa during the ICSI procedure and the initial male diagnosis before performing TESE were identified as relevant and independent parameters for live birth after TESE-ICSI.

WHAT IS KNOWN ALREADY

In reproductive medicine prediction models are used frequently to predict treatment success, but no prediction model currently exists for live birth after TESE-ICSI.

STUDY DESIGN, SIZE, DURATION

A retrospective cohort study between 2007 and 2015 in two academic hospitals including 1559 TESE-ICSI cycles. The prediction model was developed using data from one centre and validation was performed with data from the second centre.

PARTICIPANTS/MATERIALS, SETTING, METHODS

We included couples undergoing ICSI treatment with surgically retrieved sperm from the testis for the first time. In the development set we included 526 couples undergoing 1006 TESE-ICSI cycles. In the validation set we included 289 couples undergoing 553 TESE-ICSI cycles. Multivariable logistic regression models were constructed in a stepwise fashion (P < 0.2 for entry). The external validation was based on discrimination and calibration.

MAIN RESULTS AND THE ROLE OF CHANCE

We included 224 couples (22.3%) with a live birth in the development set. The occurrence of a live birth was associated with lower female age, first TESE-ICSI cycle, lower male LH, higher male testosterone, the use of motile spermatozoa for ICSI and having obstructive azoospermia as an initial suspected diagnosis. The area under the receiver operating characteristic (ROC) curve was 0.62. From validation data, the model had moderate discriminative capacity (c-statistic 0.67, 95% confidence interval: 0.62-0.72) but calibrated well, with a range from 0.06 to 0.56 in calculated probabilities.

LIMITATIONS, REASONS FOR CAUTION

We had a lack of data about the motility of spermatozoa during TESE, therefore, we used motility of the spermatozoa used for ICSI after freeze-thawing, information which is only available during treatment. We had to exclude data on paternal BMI in the model because too many missing values in the validation data hindered testing. We did not include a histologic diagnosis, which would have made our data set less heterogeneous and, finally, our model may not be applicable in centres which have a different policy for the indication for performing sperm extraction. The prognostic value of the model is limited because of a low 'area under the curve'.

WIDER IMPLICATIONS OF THE FINDINGS

This model enables the differentiation between couples with a low or high chance to reach a live birth using TESE-ICSI. As such it can aid in the counselling of patients and in clinical decision-making.

STUDY FUNDING/COMPETING INTERESTS

This study was partly supported by an unconditional grant from Merck Serono (to D.D.M.B. and K.F.) and by the Department of Obstetrics and Gynaecology of Radboud University Medical Center, Nijmegen, The Netherlands, the Department of Obstetrics and Gynaecology, Jeroen Bosch Hospital, Den Bosch, The Netherlands, and the Department of Obstetrics and Gynaecology, Academic Medical Center, Amsterdam, The Netherlands. Merck Serono had no influence in concept, design, nor elaboration of this study.

TRIAL REGISTRATION NUMBER

Not applicable.

Beneficial value of testicular sperm extraction-AgarCyto in addition to the standard testicular biopsy for diagnosis of testicular germ cell tumors in nonobstructive azoospermia

OBJECTIVE

To study whether immunohistochemical detection of germ cell neoplasia in situ (GCNIS) in AgarCytos, made of the remnants of the testicular sperm extraction (TESE) specimen, is equally accurate as in a standard testicular biopsy.

DESIGN

Prospective cohort study performed between January 2013 and May 2014.

SETTING

University hospital.

PATIENT(S)

All men with nonobstructive azoospermia (n = 197) undergoing a urological work-up followed by a unilateral or bilateral TESE for fertility treatment were consecutively included.

INTERVENTION(S)

An AgarCyto was made of the remnants of these TESE biopsies. Simultaneously a standard testicular biopsy was performed. For all cases a routine hematoxylin-eosin (H & E) staining was performed as well as immunohistochemistry (PLAP and OCT3/4) to detect GCNIS.

MAIN OUTCOME MEASURE(S)

The presence or absence of GCNIS in the TESE-AgarCyto and standard testicular biopsy.

RESULT(S)

Six men (3.0%) were diagnosed with a germ cell (pre)malignancy by immunohistochemistry. No cases were encountered in which the TESE-AgarCyto was negative, whereas the standard testicular biopsy was positive for GCNIS. In one case the TESE-AgarCyto detected a premalignancy that was missed by standard testicular biopsy. Unfortunately a standard testicular biopsy was not available for direct comparison in 50% of the GCNIS-positive patients due to various reasons.

CONCLUSION(S)

Because GCNIS is heterogeneously distributed in the testis, the TESE-AgarCyto can diagnose GCNIS even when the standard testicular biopsy is negative. Direct comparison of accuracy, however, is not reliable due to the low prevalence of GCNIS and the lack of a standard biopsy when an orchidectomy was performed simultaneously with TESE.

Gamete derivation from embryonic stem cells, induced pluripotent stem cells or somatic cell nuclear transfer-derived embryonic stem cells: state of the art

Generating gametes from pluripotent stem cells (PSCs) has many scientific justifications and several biomedical rationales. Here, we consider several strategies for deriving gametes from PSCs from mice and primates (human and non-human) and their anticipated strengths, challenges and limitations. Although the 'Weismann barrier', which separates the mortal somatic cell lineages from the potentially immortal germline, has long existed, breakthroughs first in mice and now in humans are artificially creating germ cells from somatic cells. Spermatozoa with full reproductive viability establishing multiple generations of seemingly normal offspring have been reported in mice and, in humans, haploid spermatids with correct parent-of-origin imprints have been obtained. Similar progress with making oocytes has been published using mouse PSCs differentiated in vitro into primordial germ cells, which are then cultured after xenografting reconstructed artificial ovaries. Progress in making human oocytes artificially is proving challenging. The usefulness of these artificial gametes, from assessing environmental exposure toxicity to optimising medical treatments to prevent negative off-target effects on fertility, may prove invaluable, as may basic discoveries on the fundamental mechanisms of gametogenesis.

Artificial gametes from stem cells

The generation of artificial gametes is a real challenge for the scientific community today. In vitro development of human eggs and sperm will pave the way for the understanding of the complex process of human gametogenesis and will provide with human gametes for the study of infertility and the onset of some inherited disorders. However, the great promise of artificial gametes resides in their future application on reproductive treatments for all these people wishing to have genetically related children and for which gamete donation is now their unique option of parenthood. This is the case of infertile patients devoid of suitable gametes, same sex couples, singles and those fertile couples in a high risk of transmitting serious diseases to their progeny. In the search of the best method to obtain artificial gametes, many researchers have successfully obtained human germ cell-like cells from stem cells at different stages of differentiation. In the near future, this field will evolve to new methods providing not only viable but also functional and safe artificial germ cells. These artificial sperm and eggs should be able to recapitulate all the genetic and epigenetic processes needed for the correct gametogenesis, fertilization and embryogenesis leading to the birth of a healthy and fertile newborn.

Stem cell therapeutic possibilities: future therapeutic options for male-factor and female-factor infertility?

Recent advances in assisted reproduction treatment have enabled some couples with severe infertility issues to conceive, but the methods are not successful in all cases. Notwithstanding the significant financial burden of assisted reproduction treatment, the emotional scars from an inability to conceive a child enacts a greater toll on affected couples. While methods have circumvented some root causes for male and female infertility, often the underlying causes cannot be treated, thus true cures for restoring a patient's fertility are limited. Furthermore, the procedures are only available if the affected patients are able to produce gametes. Patients rendered sterile by medical interventions, exposure to toxicants or genetic causes are unable to utilize assisted reproduction to conceive a child - and often resort to donors, where permitted. Stem cells represent a future potential avenue for allowing these sterile patients to produce offspring. Advances in stem cell biology indicate that stem cell replacement therapies or in-vitro differentiation may be on the horizon to treat and could cure male and female infertility, although significant challenges need to be met before this technology can reach clinical practice. This article discusses these advances and describes the impact that these advances may have on treating infertility.

Surgical techniques for the management of male infertility

Evaluation and surgical treatment of male infertility has evolved and expanded, now leading to more precise diagnoses and tailored treatments with diminished morbidity and greater success. Surgeries for male infertility are divided into four major categories: (i) diagnostic surgery; (ii) surgery to improve sperm production; (iii) surgery to improve sperm delivery; and (iv) surgery to retrieve sperm for use with in vitro fertilization and intracytoplasmic sperm injection (IVF-ICSI). While today we are more successful than ever in treating male infertility, pregnancy is still not always achieved likely due to factors that remain poorly understood. Clinicians treating infertility should advocate for couple-based therapy, and require that both partners have a thorough evaluation and an informed discussion before undergoing specific surgical therapies.

[Azoospermia: management and results: a series of 90 cases]

OBJECTIVE

To report our 15-year experience in managing azoospermic males at the Brest University Hospital.

PATIENTS AND METHODS

From 1996 to 2010, 90 azoospermic males were followed: 41 with non-obstructive azoospermia (NOA) and 49 with obstructive azoospermia (OA). Surgical methods proposed for retrieving sperm were Microsurgical Epididymal Sperm Aspiration (MESA) for men with OA and microdissection Testicular Sperm Extraction (mTESE) for those with NOA.

RESULTS

Spermatozoa were retrieved in 56.1% of the testicular biopsies for NOA. The embryo transfer rate per cycle for injection intracytoplasmique d'un spermatozoïde (ICSI) with epididymal spermatozoa (OA) was higher to that of ICSI with ejaculated spermatozoa (93.2% vs. 86.6%, P<0.05), but the rate was lower for ICSI with testicular sperm (NOA) (70.2% vs. 86.6%, P<0.01). The rate of clinical pregnancy per embryo transfer was 31.4% following ICSI with epididymal spermatozoa but it was of 24.2% with testicular sperm and 23.1% with ejaculated sperm.

CONCLUSION

ICSI are usually difficult in NOA because they are done with very few spermatozoa. When spermatozoa are retrieved from surgical techniques, more than 50% of the OA couples and almost 30% of the NOA couples conceived at least one child.