Semen quality before cryopreservation and after thawing in 543 patients with testicular cancer

Impact of low- or moderate-risk gonadotoxic chemotherapy prior to testicular tissue freezing on spermatogonia quantity in human (pre)pubertal testicular tissue

STUDY QUESTION

What is the impact of low- or moderate-risk gonadotoxic chemotherapy received prior to testicular tissue freezing (TTF), and of the cancer itself, on spermatogonia quantity in testicular tissue from (pre)pubertal boys?

SUMMARY ANSWER

Vincristine, when associated with alkylating agents, has an additional adverse effect on spermatogonia quantity, while carboplatin has no individual contribution to spermatogonia quantity, in testicular tissue of (pre)pubertal boys, when compared to patients who have received non-alkylating chemotherapy.

WHAT IS KNOWN ALREADY

The improved survival rates after cancer treatment necessitate the inclusion of fertility preservation procedures as part of the comprehensive care for patients, taking into consideration their age. Sperm cryopreservation is an established procedure in post-pubertal males while the TTF proposed for (pre)pubertal boys remains experimental. Several studies exploring testicular tissue of (pre)pubertal boys after TTF have examined the tubular fertility index (TFI, percentage of seminiferous tubule cross-sections containing spermatogonia) and the number of spermatogonia per seminiferous tubule cross-section (S/T). All studies have demonstrated that TFI and S/T always decrease after the introduction of chemotherapeutic agents, especially those which carry high gonadotoxic risks such as alkylating agents.

STUDY DESIGN, SIZE, DURATION

Testicular tissue samples from 79 (pre)pubertal boys diagnosed with cancer (from 6 months to 16 years of age) were cryopreserved between May 2009 and June 2014. Their medical diagnoses and previous chemotherapy exposures were recorded. We examined histological sections of (pre)pubertal testicular tissue to elucidate whether the chemotherapy or the primary diagnosis affects mainly TFI and S/T.

PARTICIPANTS/MATERIALS, SETTING, METHODS

(Pre)pubertal boys with cancer diagnosis who had been offered TTF prior to conditioning treatment for hematopoietic stem cell transplantation were included in the study. All the patients had previously received chemotherapy with low- or moderate-risk for future fertility. We have selected patients for whom the information on the chemotherapy received was complete. The quantity of spermatogonia and quality of testicular tissue were assessed by both morphological and immunohistochemical analyses.

MAIN RESULTS AND THE ROLE OF CHANCE

A significant reduction in the number of spermatogonia was observed in boys treated with alkylating agents. The mean S/T values in boys exposed to alkylating agents were significantly lower compared to boys exposed to non-alkylating agents (P = 0.018). In contrast, no difference was observed for patients treated with carboplatin as the sole administered alkylating agent compared to the group of patients exposed to non-alkylating agents. We observed an increase of S/T with age in the group of patients who did not receive any alkylating agent and a decrease of S/T with age when patients received alkylating agents included in the cyclophosphamide equivalent dose (CED) formula (r = 0.6166, P = 0.0434; r = -0.3759, P = 0.0036, respectively). The TFI and S/T decreased further in the group of patients who received vincristine in combination with alkylating agents (decrease of 22.4%, P = 0.0049 and P < 0.0001, respectively), but in this group the CED was also increased significantly (P < 0.0001). Multivariate analysis, after CED adjustment, showed the persistence of a decrease in TFI correlated with vincristine administration (P = 0.02).

LIMITATIONS, REASONS FOR CAUTION

This is a descriptive study of testicular tissues obtained from (pre)pubertal boys who were at risk of infertility. The study population is quite heterogeneous, with a small number of patients in each sub-group. Our results are based on comparisons between patients receiving alkylating agents compared to patients receiving non-alkylating agents rather than chemotherapy-naive patients. The French national guidelines for fertility preservation in cancer patients recommend TTF before highly gonadotoxic treatment. Therefore, all the patients had received low- or moderate-risk gonadotoxic chemotherapy before TTF. Access to testicular tissue samples from chemotherapy-naive patients with comparable histological types of cancer was not possible. The functionality of spermatogonia and somatic cells could not be tested by transplantation or in vitro maturation due to limited sample sizes.

WIDER IMPLICATIONS OF THE FINDINGS

This study summarizes the spermatogonial quantity of (pre)pubertal boys prior to TTF. We confirmed a negative correlation between the cumulative exposure to alkylating agents and spermatogonial quantity. In addition, the synergistic use of vincristine in combination with alkylating agents showed a cumulative deleterious effect on the TFI. For patients for whom fertility preservation is indicated, TTF should be proposed for chemotherapy with a predicted CED above 4000 mg/m2. However, the data obtained from vincristine and carboplatin use should be confirmed in a subsequent study including more patients.

STUDY FUNDING/COMPETING INTEREST(S)

This study had financial support from a French national research grant PHRC No. 2008/071/HP obtained by the French Institute of Cancer and the French Healthcare Organization. The sponsors played no role in the study. The authors declare no conflicts of interest.

TRIAL REGISTRATION NUMBER

N/A.

Effect of Pre-Incubation of Cryopreserved Sperm with either Kisspeptin or Glutathione to Mitigate Freeze-Thaw Damage

Background

Sperm cryopreservation reduces sperm quality. Kisspeptin (KP) has beneficial effects on sperm functions. This study compares the effect of KP and Glutathione (GSH) on mitigating the detrimental effects of the freeze-thaw cycle on sperm.

Methods

An experimental study was conducted in Birjand (Iran) during 2018-2020. Thirty normal swim-up semen samples were treated with Ham's F10 medium (negative control), 1 mM GSH (positive control), or KP (10 µM) for 30 min before freezing. The motility, acrosome reaction, capacitation, and DNA quality of the frozen-thawed sperms were assessed according to the WHO guidelines. Statistical analysis was performed using paired t test, one-way analysis of variance, and least significant difference.

Results

Pre-incubation with KP significantly increased the percentage of sperm motility (34.00±6.7, P=0.003) compared to the control (20.44±7.4) and GSH-treated (31.25±12.2) aliquots. The frequency of non-capacitated spermatozoa was significantly higher in the KP-treated group (98.73%) than in the control (96.46%) and GSH-treated (96.49%) aliquots (P<0.001). The percentage of acrosome-intact spermatozoa in the KP-treated group (77.44%) was significantly higher than the control (74.3%) and GSH-treated (74.54%) groups (P<0.001). The sperm frequency with normal histone in the KP-treated group (51.86%) and with normal protamine (65.39%) was significantly higher than the controls (P=0.001 and P=0.002, respectively). The percentage of TUNEL-positive sperm was significantly lower in the KP-treated group (9.09±2.71) than both GSH-treated (11.22±2.73) and control (11.31±2.2) groups (both P=0.002).

Conclusion

Pre-incubation with KP protects sperm motility and DNA integrity from the detrimental effect of the freeze-thaw cycle. KP is suitable as a pre-treatment to control sperm quality during freezing-thawing.

Cryopreservation of Human Spermatozoa: Functional, Molecular and Clinical Aspects

Cryopreservation is an expanding strategy to allow not only fertility preservation for individuals who need such procedures because of gonadotoxic treatments, active duty in dangerous occupations or social reasons and gamete donation for couples where conception is denied, but also for animal breeding and preservation of endangered animal species. Despite the improvement in semen cryopreservation techniques and the worldwide expansion of semen banks, damage to spermatozoa and the consequent impairment of its functions still remain unsolved problems, conditioning the choice of the technique in assisted reproduction procedures. Although many studies have attempted to find solutions to limit sperm damage following cryopreservation and identify possible markers of damage susceptibility, active research in this field is still required in order to optimize the process. Here, we review the available evidence regarding structural, molecular and functional damage occurring in cryopreserved human spermatozoa and the possible strategies to prevent it and optimize the procedures. Finally, we review the results on assisted reproduction technique (ARTs) outcomes following the use of cryopreserved spermatozoa.

Effect of Malignancy on Semen Parameters

Purpose: We aimed to examine how various types of cancer, classified histologically, affect semen quality. Methods: The study group included 313 patients who were diagnosed with cancer and reached for a sperm cryopreservation before a gonadotoxic treatment (PG-Tx group). Their semen parameters were compared to those of two control groups: (a) individuals who attended a fertility investigation and were found to be above the limit of the lower reference value of the WHO 2010 manual (ARL group), and (b) fertile men, whose semen parameters were obtained from the dataset of the WHO 2020 manual. Results: Semen quality was significantly poorer in the PG-Tx group than in the ARL group. Differences included a 65.6% decrease in concentration, a 12.1% decrease in volume, a 72.7% decrease in total count, and a 33.0%, 22.2%, and 24.7% decrease in total motility, rapid motility, and progressive motility, respectively. Linear regression models comparing the PG-Tx and ARL groups revealed that the maximum reduction in total motility and concentration was in men with germ-cell tumors, whereas the minimum reduction was in hematological tumors. Similarly, all sperm quality parameters were significantly lower in the PG-Tx group than in the fertile-men group (p < 0.0001). Conclusions: While the effect of malignancy on semen parameters is debatable, we found that all examined types of cancer significantly impaired sperm quality parameters. Although the median of most semen parameters of patients with cancer were still in the normal WHO range, their fifth percentile, represents men with a delayed time to pregnancy.

Fertility Preservation and Restoration Options for Pre-Pubertal Male Cancer Patients: Current Approaches

Fertility preservation for prepubertal male patients undergoing gonadotoxic therapies, potentially depleting spermatogonial cells, is an expanding necessity, yet most of the feasible options are still in the experimental phase. We present our experience and a summary of current and novel possibilities regarding the different strategies to protect or restore fertility in young male patients, before proceeding with chemotherapy or radiotherapy for malignances or other diseases. Adult oncological patients should always be counselled to cryopreserve the semen before starting treatment, however this approach is not suitable for prepubertal boys, who aren't capable to produce sperm yet. Fortunately, since the survival rate of pediatric cancer patients has skyrocketed in the last decade and it's over 84%, safeguarding their future fertility is becoming a major concern for reproductive medicine. Surgical and medical approaches to personalize treatment or protect the gonads could be a valid first step to take. Testicular tissue autologous grafting or xenografting, and spermatogonial stem cells (SSCs) transplantation, are the main experimental options available, but spermatogenesis in vitro is becoming an intriguing alternative. All of these methods feature both strong and weak prospects. There is also relevant controversy regarding the type of testicular material to preserve and the cryopreservation methods. Since transplanted cells are bound to survive based on SSCs number, many ways to enrich their population in cultures have been proposed, as well as different sites of injection inside the testis. Testicular tissue graft has been experimented on mice, rabbits, rhesus macaques and porcine, allowing the birth of live offspring after performing intracytoplasmic sperm injection (ICSI), however it has never been performed on human males yet. In vitro spermatogenesis remains a mirage, although many steps in the right direction have been performed. The manufacturing of 3D scaffolds and artificial spermatogenetic niche, providing support to stem cells in cultures, seems like the best way to further advance in this field.

Association of malignant neoplasms with semen quality in Guangdong province, China: A propensity score matching analysis

BACKGROUND

Previous studies have reported lower semen quality in malignant neoplasm patients before antineoplastic treatments, but the adverse effects of malignant neoplasms on semen quality have rarely been quantitatively evaluated. In addition, due to the lack of a comparable control group and limited types of studied malignant neoplasms, the results remain inconsistent and inconclusive.

OBJECTIVES

To quantitatively evaluate the potential adverse effects of specific malignant neoplasms on semen quality.

MATERIALS AND METHODS

We conducted a cross-sectional study to investigate 445 malignant neoplasm patients undergoing sperm cryopreservation for fertility preservation in Guangdong province, China during 2016-2019. A propensity score matching method was used to select a comparable control group from 9170 sperm donation volunteers. Each subject was analyzed for semen quality. Multivariate linear regression models were employed to assess the association between malignant neoplasm and semen quality.

RESULTS

Using the propensity score matching method, 413 (92.8%) malignant neoplasm patients were successfully matched with 798 sperm donation volunteers. Overall, malignant neoplasms were significantly associated with a 0.3 ml, 17.1 × 10⁶ /ml, 67.6 × 10⁶ , 9.8%, 10.2%, and 6.4% reduction in semen volume, sperm concentration, total sperm number, total motility, progressive motility, and normal forms, respectively. Malignant neoplasm of testis, nasopharynx and digestive organs, Hodgkin lymphoma, non-Hodgkin lymphoma, and leukemia were significantly associated with a reduction in sperm motility and normal forms, while malignant neoplasm of testis, Hodgkin lymphoma, and leukemia were also significantly associated with reduced sperm concentration and/or total sperm number. The reduction in sperm concentration and total sperm number associated with malignant neoplasms was significantly greater in subjects < 30 years.

DISCUSSION AND CONCLUSION

We found that malignant neoplasms were significantly associated with a reduction in semen quality, which varied across the type of malignant neoplasms. Our results highlight the needs to examine semen quality for young malignant neoplasm patients, especially those who are expected to conceive.

Impaired semen quality in trans women: prevalence and determinants

STUDY QUESTION

What is the semen quality in trans women at time of fertility preservation, prior to the start of gender-affirming hormone treatment?

SUMMARY ANSWER

Before the start of gender-affirming hormone treatment, semen quality in trans women was already strongly decreased compared to the general population.

WHAT IS KNOWN ALREADY

Hormone treatment for -trans women (birth-assigned males, female gender identity) consists of anti-androgens combined with estrogens in order to achieve feminization and it is accompanied by a loss of reproductive capability. Trans women can opt for semen cryopreservation prior to their medical transition to retain the possibility to parent genetically related offspring. Post-thaw semen parameters determine which ART can be used. Knowledge of semen quality and the factors negatively influencing semen parameters in trans women are important to improve semen quality before fertility preservation.

STUDY DESIGN, SIZE, DURATION

A retrospective cohort study was performed between 1972 and 2017. In total, 260 trans women were included for this study. Due to the study design, there was no loss to follow-up or attrition.

PARTICIPANTS/MATERIALS, SETTING, METHODS

We studied the quality of the preserved semen in trans women, prior to their medical transition, who visited our gender clinic. Semen parameters were collected, as well as data on age, alcohol consumption, smoking, cannabis use, BMI, previous use of estrogens or anti-androgens and endocrine laboratory results. Semen parameters were categorized using reference values for human semen of the World Health Organization (WHO) and compared with data from the general population. Logistic regression analyses were performed to analyze the extent to which factors known to have a negative impact on semen quality in the general population explained the impaired semen quality in the cohort.

MAIN RESULTS AND THE ROLE OF CHANCE

The cohort consisted of 260 trans women between the age of 16 and 52 years. Semen quality in trans women was significantly decreased compared to WHO data from the general population. In total, 21 trans women had an azoospermia and median semen parameters for the remaining trans women and the general population, respectively, were as follows: volume 2.7 and 3.2 ml (P < 0.05), sperm concentration 40 and 64 million/ml (P < 0.05), total sperm number 103 and 196 million (P < 0.05) and progressive motility 41% and 57% (P < 0.05). Smoking (odds ratio (OR) 2.35 (95% CI 1.06–5.21)) and a higher age at time of fertility preservation (OR 1.04 (95% CI 1.00–1.08)) were found to correlate with an impaired progressive motility. Twelve trans women reported to have used anti-androgens and estrogens, and all had discontinued for at least 3 months prior to the first attempt for semen cryopreservation. No correlation was found between previous gender-affirming hormone use and decreased semen parameters. The median post-thaw total motile sperm count was 1.0 million per vial (interquartile range 0.1–3.1) and in only 26.4% of thawed semen samples was the quality adequate for a minimally invasive IUI.

LIMITATIONS, REASONS FOR CAUTION

Limitations include the retrospective design and insufficient data on transgender-specific factors, such as bringing the testes into the inguinal position (tucking), wearing tight underwear and low masturbation frequency.

WIDER IMPLICATIONS OF THE FINDINGS

Semen quality in trans women was decreased compared to the general population, which could not be explained by known risk factors, such as BMI, alcohol consumption, cannabis use, gender-affirming hormone use or abnormal endocrine laboratory results. Although a negative impact of smoking was observed, it was insufficient to explain the overall decreased semen quality in this cohort. Since low pre-freeze semen quality results in an even lower post-thaw semen quality, the majority of trans women and their female partner or surrogate may need an invasive and burdensome treatment to establish a pregnancy.

STUDY FUNDING/COMPETING INTEREST(S)

For this study, no external funding was obtained and there were no competing interests.

TRIAL REGISTRATION NUMBER

NA.

Dysregulation of Key Proteins Associated with Sperm Motility and Fertility Potential in Cancer Patients

Cancer has adverse effects on male reproductive health. Conventional semen analysis does not explain the molecular changes in the spermatozoa of cancer patients. Currently, proteomics is being widely used to identify the fertility-associated molecular pathways affected in spermatozoa. The objective of this study was to evaluate the sperm proteome of patients with various types of cancer. Cryopreserved semen samples from patients (testicular cancer, n = 40; Hodgkin’s disease, n = 32; lymphoma, n = 20; leukemia, n = 17) before starting therapy were used for proteomic analysis, while samples from fertile donors (n = 19) were included as controls. The proteomic profiling of sperm was carried out by liquid chromatography-tandem mass spectrometry, and differentially expressed proteins involved in the reproductive processes were validated by Western blotting. Bioinformatic analysis revealed that proteins associated with mitochondrial dysfunction, oxidative phosphorylation, and Sirtuin signaling pathways were dysregulated in cancer patients, while oxidative phosphorylation and tricarboxylic acid cycle were predicted to be deactivated. Furthermore, the analysis revealed dysregulation of key proteins associated with sperm fertility potential and motility (NADH:Ubiquinone oxidoreductase core subunit S1, superoxide dismutase 1, SERPINA5, and cytochrome b-c1 complex subunit 2) in the cancer group, which were further validated by Western blot. Dysfunctional molecular mechanisms essential for fertility in cancer patients prior to therapy highlight the potential impact of cancer phenotype on male fertility.

Use and Effectiveness of Sperm Cryopreservation for Adolescents and Young Adults: A 37-Year Bicentric Experience

Aim: Sperm cryopreservation (SCP) should be offered to every adolescent before gonadotoxic treatment, but experience in this age range is still relatively limited. The goal of this study is to assess how to optimize this procedure. Methods and Patients: One hundred thirty-three patients between 12 and 20 years old, who underwent SCP between 1980 and 2017, were included. Baseline data (age, indication for SCP, and semen parameters at freezing) and follow-up data (outcome of sperm straws and follow-up of sperm quality) were collected and analyzed. Results: SCP is feasible from the age of 12. Semen assessment parameters at this age were close to parameters of adults. However, we observed quantitative impairments in testicular tumors and qualitative impairments in leukemia and bone marrow failure. Four patients (3%) used their cryopreserved semen for medically assisted reproduction, 15 patients died (11.3%), 18 asked for destruction of their straws (13.5%), and nine samples were destroyed because of lack of news (6.8%). Very few patients underwent a sperm analysis after treatment. Conclusions: SCP is an efficient, still underused, procedure for adolescents and young adults. Cryopreserved sperm is rarely used and rarely destroyed, but studies with a longer follow-up are needed to better assess these observations. Follow-up with a specialist of reproductive medicine is valuable for better information of the patient.

Progress in translational reproductive science: testicular tissue transplantation and in vitro spermatogenesis

Since the birth of the first child conceived via in vitro fertilization 40 years ago, fertility treatments and assisted reproductive technology have allowed many couples to reach their reproductive goals. As of yet, no fertility options are available for men who cannot produce functional sperm, but many experimental therapies have demonstrated promising results in animal models. Both autologous (stem cell transplantation, de novo morphogenesis, and testicular tissue grafting) and outside-the-body (xenografting and in vitro spermatogenesis) approaches exist for restoring sperm production in infertile animals with varying degrees of success. Once safety profiles are established and an ideal patient population is chosen, some of these techniques may be ready for human experimentation in the near future, with likely clinical implementation within the next decade.

Altered Molecular Pathways in the Proteome of Cryopreserved Sperm in Testicular Cancer Patients before Treatment

Testicular cancer (TC) represents the most common cancer affecting men within the reproductive age and is often accompanied by major disturbances in semen parameters. Cryopreservation is recommended in these patients before initiating cancer treatment. Currently, there are no studies reporting the molecular mechanisms associated with altered semen quality in these men. The main objective of this study was to compare the sperm proteome of normozoospermic (motility >40%) and asthenozoospermic (motility <40%) TC patients with normozoospermic infertile men without cancer (control group). Pooled sperm samples from normozoospermic (n = 20), asthenozoospermic (n = 11) TC, and a control group (n = 9) were used for quantitative global proteomic profiling using liquid chromatography-tandem mass spectrometry. A total of 1085, 846, and 982 proteins were identified in normozoospermic TC, asthenozoospermic TC, and control groups, respectively. Functional analysis revealed mitochondrial dysfunction and altered cellular pathways in both normozoospermic and asthenozoospermic TC patients. Comparison of pathway analysis showed no significant difference in fertility-associated proteins/mechanism between the normozoospermic TC patients and infertile men. Western blot analysis revealed under-expression of NDUFS1 associated with mitochondrial dysfunction and overexpression of CD63 involved in sperm maturation in both normozoospermic and asthenozoospermic TC patients. Our proteomic results confirm that defective cellular pathways are associated with reproductive functions in both normozoospermic and asthenozoospermic TC patients before the start of cancer treatment.

Sperm cryopreservation of transgender individuals: trends and findings in the past decade

OBJECTIVES

Awareness and acceptance of transgenderism have increased in the last two decades. There is limited literature regarding the incidence and semen characteristics of transwomen banking spermatozoa. We sought to assess the incidence of sperm cryopreservation of transgender individuals compared with the cisgender population in the last 10 years. Semen parameters were also compared between the two groups.

MATERIALS AND METHODS

We performed a retrospective analysis of sperm cryopreservation performed at a single center from 2006 through 2016. Using available data on indications for banking and prior hormonal therapy status, we isolated healthy transgender and cisgender cohorts for semen parameter comparison. Linear regression was used to compare the incidence trends. Semen parameters were compared using the generalized estimating equations method. The rates of semen parameter abnormality of each group were compared using chi-square test. Semen parameter abnormalities were defined using WHO 2010 reference values.

RESULTS

We analyzed 194 transgender samples and 2327 cisgender samples for a total of 84 unique transgender sperm bankers and 1398 unique cisgender sperm bankers. The number of transgender sperm bankers increased relative to cisgender sperm bankers from 2006 to 2016. Following exclusion of cisgender sperm bankers with health issues that might impact semen quality and transgender sperm bankers with known prior hormonal therapy, we compared the semen parameters of 141 healthy cisgender sperm bankers and 78 healthy transgender sperm bankers. The transgender sperm bankers demonstrated lower sperm concentration, total motile sperm count, and post-thaw sperm parameters. The transgender sperm bankers also demonstrated a higher incidence of oligozoospermia.

CONCLUSIONS

This is the largest report to date on the incidence of transgender sperm cryopreservation and comparison of semen characteristics with cisgender sperm bankers. The data reveal an increased incidence of transgender sperm banking as well as poorer semen parameters of transgender individuals compared with cisgender controls.

Sperm imprinting integrity in seminoma patients?

BACKGROUND

Testicular germ cell tumor such as seminoma is strongly associated with male reproductive problems commonly associated with the alteration of sperm parameters as described in testicular dysgenesis syndrome. Interestingly, numerous studies have reported that the precursor of germ cell cancer, germ cell neoplasia in situ (GCNIS), present similarities to fetal gonocytes, specifically characterized by global DNA hypomethylation particularly on imprinting sequences. These disorders may have a common origin derived from perturbations of embryonal programming during fetal development. Presently, there is no available information concerning the sperm DNA methylation patterns of testicular cancer patients. For the first time, we evaluated the sperm imprinting of seminoma patients. A total of 92 cryopreserved sperm samples were included, 31 before seminoma treatment (S): 23 normozoospermic (SN) and 8 oligozoospermic (SO) and 61 sperm controls samples: 31 normozoospermic (N) and 30 oligozoospermic (O). DNA methylation levels of seven differentially methylated regions (DMRs) of imprinted genes [H19/IGF2: IG-DMR (CTCF3 and CTCF6 of H19 gene); IGF2-DMRs (DMR0 and DMR2); MEG3/DLK1:IG-DMR; SNURF:TSS-DMR; KCNQ1OT1:TSS-DMR] were assessed by pyrosequencing. All comparative analyses were adjusted for age.

RESULTS

Comparisons of sperm DNA methylation levels between seminoma (S) and normozoospermic (N) samples showed a significant difference for the SNURF sequence (p = 0.017), but after taking into account the sperm parameters, no difference was observed. However, we confirmed a significant association between oligozoospermia (O) and imprinting defects for H19/IGF2-CTCF6 (p = 0.001), MEG3/DLK1 (p = 0.017), IGF2-DMR2 (p = 0.022), and SNURF (p = 0.032) in comparison with control groups (N).

CONCLUSIONS

This study highlights the high risk of sperm imprinting defects in cases of oligozoospermia and shows for the first time that seminoma patients with normal spermatogenesis present sperm imprinting integrity. These data suggest a low probability of the involvement of a common imprinting defect in fetal cells leading to both TGCT and subfertility.