Genetic profiling of azoospermic men to identify the etiology and predict reproductive potential

PURPOSE

To identify germline mutations related to azoospermia etiology and reproductive potential of surgically retrieved spermatozoa, and to investigate the feasibility of predicting seminiferous tubule function of nonobstructive azoospermic men by transcriptomic profiling of ejaculates.

MATERIALS AND METHODS

Sperm specimens were obtained from 30 men (38.4 ± 6 years) undergoing epididymal sperm aspiration for obstructive azoospermia (OA, n = 19) acquired by vasectomy, or testicular biopsy for nonobstructive azoospermia (NOA, n = 11). To evaluate for a correlation with azoospermia etiology, DNAseq was performed on surgically retrieved spermatozoa, and cell-free RNAseq on seminal fluid (n = 23) was performed to predict spermatogenesis in the seminiferous tubule.

RESULTS

Overall, surgically retrieved sperm aneuploidy rates were 1.7% and 1.8% among OA and NOA cohorts, respectively. OA men carried housekeeping-related gene mutations, while NOA men displayed mutations on genes involved in crucial spermiogenic functions (AP1S2, AP1G2, APOE). We categorized couples within each cohort according to ICSI clinical outcomes to investigate genetic causes that may affect reproductive potential. All OA-fertile men (n = 9) carried mutations in ZNF749 (sperm production), whereas OA-infertile men (n = 10) harbored mutations in PRB1, which is essential for DNA replication. NOA-fertile men (n = 8) carried mutations in MPIG6B (stem cell lineage differentiation), whereas NOA-infertile individuals (n = 3) harbored mutations in genes involved in spermato/spermio-genesis (ADAM29, SPATA31E1, MAK, POLG, IFT43, ATG9B) and early embryonic development (MBD5, CCAR1, PMEPA1, POLK, REC8, REPIN1, MAPRE3, ARL4C). Transcriptomic assessment of cell-free RNAs in seminal fluid from NOA men allowed the prediction of residual spermatogenic foci.

CONCLUSIONS

Sperm genome profiling provides invaluable information on azoospermia etiology and identifies gene-related mechanistic links to reproductive performance. Moreover, RNAseq assessment of seminal fluid from NOA men can help predict sperm retrieval during testicular biopsies.

High sperm DNA fragmentation: do we have robust evidence to support antioxidants and testicular sperm extraction to improve fertility outcomes? a narrative review

To date, infertility affects 10% to 15% of couples worldwide. A male factor is estimated to account for up to 50% of cases. Oral supplementation with antioxidants could be helpful to improve sperm quality by reducing oxidative damage. At the same time, there is a growing interest in the literature on the use of testicular sperm in patients with high DNA fragmentation index (DFI). This narrative review aims to evaluate the effectiveness of supplementation of oral antioxidants in infertile men with high DFI compared to testicular sperm retrieval. The current evidence is non-conclusive because of serious risk of bias due to small sample sizes and statistical methods. Further large well-designed randomised placebo-controlled trials are still required to clarify the exact role of these to different therapeutic approaches.

Azoospermic Men with a History of Cryptorchidism Treated by Orchiopexy Have Favorable Outcomes after Testicular Sperm Extraction: A Systematic Review and Meta-Analysis

PURPOSE

This systematic review and meta-analysis investigated the sperm retrieval rate (SRR) and pregnancy rate after testicular sperm extraction in men with azoospermia and those with a history of cryptorchidism treated by orchiopexy.

MATERIALS AND METHODS

The SRR and clinical pregnancy rate were investigated. We performed a sub-analysis that included factors such as bilaterality, age, and idiopathic non-obstructive azoospermia (iNOA). The analysis comprised 13 studies from January 1995 to July 2021. The data sources were PubMed/MEDLINE, Embase, and the Cochrane Library included "cryptorchidism", "orchidopexy", "azoospermia", and "testicular sperm extraction".

RESULTS

The overall mean SRR was 63.3% (95% confidence interval [CI], 57.6%-68.6%; I²=62.4%), and the overall mean clinical pregnancy rate was 30.1% (95% CI, 22.6%-38.8%; I²=69.9%). The meta-analysis comparing the SRR, there was no significant difference between patients with a history of bilateral and unilateral orchiopexy (relative risk [RR]=1.02; 95% CI, 0.89-1.16; p=0.79). Orchiopexy performed under the age of 10 years showed significantly increased SRR compared to the age of over 10 years (RR=1.25; 95% CI, 1.06-1.47; p=0.008). Azoospermic men with a history of cryptorchidism treated by orchiopexy had significantly higher SRR than iNOA (RR=1.90; 95% CI, 1.40-2.58; p<0.0001).

CONCLUSIONS

Men with azoospermia and a history of cryptorchidism treated by orchiopexy had significantly higher SRR than those with iNOA after testicular sperm extraction. Furthermore, patients who underwent orchiopexy before the age of ten years had significantly higher SRR than patients operated at an older than the age of ten years.

Testosterone levels among non-obstructive azoospermic patients 2 years after failed bilateral microdissection testicular sperm extraction: a nested case-cohort study

PURPOSE

To define the risk of hypogonadism following microdissection testicular sperm extraction in cases of non-obstructive azoospermia. While sperm retrieval by open testicular sperm extraction can be associated with an increased risk of hypogonadism, there is limited data addressing which procedures and which patients harbor the greatest risk.

METHODS

We report on a community-acquired, nested, case-cohort of non-obstructive azoospermic patients referred to one clinic after failed bilateral microdissection testicular sperm extraction. Patients were health-matched (1:2) to surgically naïve controls and divided into 2 cohorts based on risk factors for hypogonadism. Among microdissection patients, we compared total testosterone and gonadotropin levels before and > 6 months after surgery. Biochemical hypogonadism was defined as a total serum testosterone level ≤ 300 ng/dL. Hormone levels were compared to risk-matched controls. Comparative statistics were used to assess hormone levels within and between cohorts.

RESULTS

There were no significant differences in baseline testosterone levels between microdissection patients (n = 26) and risk-matched controls (n = 52). At a mean of 26 months (range 6.2-112.8) post-procedure, mean testosterone levels decreased significantly (73 ng/dL or 16%; CI - 27, - 166; p < 0.01, paired t-test). Among microdissection patients with baseline testosterone > 300 ng/dL, 8/22 (36%) experienced hypogonadism post-procedure. There was a corresponding increase in follicle stimulating hormone (p = 0.05) and a trending increase in luteinizing hormones (p = 0.10).

CONCLUSION

A durable decrease in testosterone levels occurs after failed microdissection testicular sperm extraction regardless of baseline risk of hypogonadism. In addition, a significant proportion of eugonadal patients will become hypogonadal after failed testicular microdissection procedures.

Contribution of serum anti-Müllerian hormone in the management of azoospermia and the prediction of testicular sperm retrieval outcomes: a study of 155 adult men

Background

Testicular sperm extraction (TESE) is the method of choice for recovering spermatozoa in patients with azoospermia. However, the lack of reliable biomarkers makes it impossible to predict sperm retrieval outcomes at TESE. To date, little attention has been given to anti-Müllerian hormone (AMH) serum levels in adult men with altered spermatogenesis. In this study we aimed to investigate whether serum concentrations of AMH and the AMH to total testosterone ratio (AMH/T) might be predictive factors for sperm retrieval outcomes during TESE in a cohort of 155 adult Caucasian men with azoospermia.

Results

AMH serum levels were significantly lower in nonobstructive azoospermia (NOA) that was unexplained, cryptorchidism-related, cytotoxic and genetic (medians [pmol/l] = 30.1; 21.8; 26.7; 7.3; and p = 0.02; 0.001; 0.04; <0.0001, respectively]) compared with obstructive azoospermia (OA) (median = 44.8 pmol/l). Lowest values were observed in cases of genetic NOA (p < 0.0001, compared with unexplained NOA) and especially in individuals with non-mosaic Klinefelter syndrome (median = 2.3 pmol/l, p <0.0001). Medians of AMH/T values were significantly lower in genetic NOA compared to unexplained, cryptorchidism-related NOA as well as OA. Only serum concentrations of AMH differed significantly between positive and negative groups in men with non-mosaic Klinefelter syndrome. The optimal cut-off of serum AMH was set at 2.5 pmol/l. The sensitivity, specificity, positive predictive value, negative predictive value and accuracy of this cut-off to predict negative outcomes of SR were 100 %, 76.9 %, 66.6 %, 100 and 84.2 %, respectively.

Conclusions

Serum AMH levels, but not AMH/T values, are a good marker for Sertoli and germ cell population dysfunction in adult Caucasian men with non-mosaic Klinefelter syndrome and could help us to predict negative outcomes of SR at TESE with 100 % sensitivity when serum levels of AMH are below 2.5 pmol/l.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12610-021-00133-9.

Effect of in vitro testicular spermatozoa culture on pregnancy outcomes: an experience at a single university hospital

Background

There are no guidelines for the optimal incubation time or temperature to improve pregnancy outcomes in testicular sperm extraction-intracytoplasmic sperm injection (TESE-ICSI) cycles. We aimed to evaluate whether a 24-hour in vitro culture of testicular spermatozoa affects pregnancy outcomes in TESE-ICSI cycles.

Methods

This was a retrospective study of 83 TESE-ICSI cycles using testicular spermatozoa in 46 couples with male partners suffering from nonobstructive or obstructive azoospermia. Sperm retrieval was performed either on the oocyte retrieval (OR) day (65 cycles in 33 couples; group A) or on the day before OR (18 cycles in 13 couples; group B) followed by in vitro culture for 24 hours. The clinical characteristics and pregnancy outcomes, including the number of retrieved oocytes, fertilization rates, embryo transfer rates, implantation and clinical pregnancy rates, were compared between the two groups.

Results

There were no differences in terms of clinical characteristics except for the levels of luteinizing hormone (LH) in males. Group B had higher LH levels than group A (4.56±1.24 IU/L vs. 3.67±1.07 IU/L, p=0.017). Group B showed higher fertilization rate (72.4%±32.1% vs. 59.2%±21.7%, p=0.045), implantation rate (35.0%±34.1% vs. 14.0%±21.5%, p=0.010), pregnancy rate per cycle (80% vs. 39%, p=0.033), and clinical pregnancy rate per cycle (80% vs. 37.5%, p=0.024) than those of group A.

Conclusion

Testicular sperm retrieval performed on the day before OR followed by in vitro culture can potentially improve pregnancy outcomes.

Informational needs of couples undergoing intracytoplasmic sperm injection with surgical sperm retrieval: A qualitative study

OBJECTIVE

Infertile couples consider patient information a very important dimension of patient-centred care. Although testicular sperm extraction (TESE) followed by intracytoplasmic sperm injection (ICSI) has long been offered to infertile couples, little is known about couples' informational needs. The aim of this study was to identify the informational needs of couples undergoing TESE and ICSI, including information content and the channels providing the information as a first step to improve patient-centred care.

STUDY DESIGN

We conducted a qualitative study consisting of semi-structured interviews with 11 couples. The topic guide was based on a literature review and interviews with an expert panel. The number of interviews was determined with data saturation. The data were analysed using a constant comparative method.

RESULTS

The couples needed information about many topics. They considered information about the success rates of the treatment, an explanation of the treatment procedure, and other patient experiences the most important. Regarding information channels, the couples preferred face-to-face information, but they also valued a leaflet, website, or an online application, especially when it is personalized or providing interactive functionalities.

CONCLUSION

We obtained in-depth insight into the information needs of couples undergoing TESE and ICSI. The results of this study give fertility clinics an opportunity to develop patient information that meets the needs of their patients and thus improve patient-centred fertility care.

High Sperm DNA Damage: Does Testicular Sperm Make Sense?

Sperm DNA damage reduces pregnancy rates in couples undergoing in vitro fertilization (IVF). Because it has been shown that testicular sperm have lower DNA damage than ejaculated sperm, it is an attractive idea to consider using testicular sperm for IVF for men with high sperm DNA damage. In fact, there are multiple centers throughout the world now offering sperm retrieval for IVF to manage this condition. However, there is insufficient evidence to conclude that testicular sperm improves pregnancy/live birth rates. Further studies are required before offering sperm retrieval as a standard of care to manage high sperm DNA damage.

Successful onco-testicular sperm extraction from a testicular cancer patient with a single testis and azoospermia

Onco-testicular sperm extraction is used to preserve fertility in patients with bilateral testicular tumors and azoospermia. We report the case of a testicular tumor in the solitary testis of a patient who had previously undergone successful contralateral orchiectomy and whose sperm was preserved by onco-testicular sperm extraction. A 35-year-old patient presented with swelling of his right scrotum that had lasted for 1 month. His medical history included a contralateral orchiectomy during childhood. Ultrasonography revealed a mosaic echoic area in his scrotum, suggesting a testicular tumor. The lesion was palpated within the normal testicular tissue along its edge and semen analysis showed azoospermia. Radical inguinal orchiectomy and onco-testicular sperm extraction were performed simultaneously. Motile spermatozoa were extracted from normal seminiferous tubules under microscopy and were frozen. Eventual intracytoplasmic sperm injection using the frozen spermatozoa is planned. Onco-testicular sperm extraction is an important fertility preservation method in patients with bilateral testicular tumors or a history of a previous contralateral orchiectomy.

Microdissection testicular sperm extraction in Japanese patients with persistent azoospermia after chemotherapy

BACKGROUND

Combinations of surgery, radiation therapy, and chemotherapy can achieve high remission rates in patients with cancer, but these treatments can have damaging effects on spermatogenesis. In particular, cytotoxic chemotherapy may lead to irreversible spermatogenic dysfunction. Microdissection testicular sperm extraction (micro-TESE) is the only method that can address infertility in cancer survivors with persistent postchemotherapy azoospermia.

METHODS

We included 66 Japanese patients with postchemotherapy azoospermia who underwent micro-TESE for sperm retrieval in this analysis. Age, oncology data, hormone profiles, and outcomes of micro-TESE and subsequent intracytoplasmic sperm injections (ICSIs) were reviewed.

RESULTS

The common disease in our patients was testicular cancer (21 patients), followed by acute lymphoblastic leukemia and Hodgkin's lymphoma (nine patients). In this cohort of 66 patients, sperm was successfully retrieved in 31 patients (47 %), and clinical pregnancy occurred in 23 cases (35 %). The live birth rate was 27 %. No significant differences in sperm retrieval, clinical pregnancy, and live birth rates were seen between testicular cancer, Hodgkin's lymphoma, non-Hodgkin's lymphoma, acute lymphoblastic leukemia, acute myeloid leukemia, or sarcoma cases. Multiple logistic regression analysis showed that the chance of retrieving sperm during micro-TESE could not be predicted by any variable.

CONCLUSIONS

Cryopreservation of sperm should be offered before any gonadotoxic chemotherapy takes place. However, micro-TESE and subsequent ICSI could be effective treatment options for patients with persistent postchemotherapy azoospermia whose sperm were not frozen before therapy. Our results suggest that micro-TESE-ICSI could benefit 27 % of such Japanese patients.