Changes of Sperm Parameters Along Time Among Groups of Different Qualities.

BACKGROUND: Male infertility is solely responsible for approximately 20% of all infertility in couples. Various factors have been proposed as having a negative effect on sperm quality; however, the reasons for the global decline in sperm parameters during the last few decades are still controversial. OBJECTIVES: To investigate the fluctuations of semen parameters (sperm concentration, motility, and morphology) in three sperm quality groups and to examine the trends of those parameters in the same men over time. RESULTS: Our data showed deterioration in all semen parameters assessed in the group of men originally considered as having normal semen values according to the 2010 criteria of the World Health Organization. In contrast, we found significant improvement over time in all semen parameters in the group of men with severe oligo-terato-asthenozoospermia. CONCLUSIONS: Our results suggest that, although there were changes in sperm quality over time in the groups assessed, the clinical significance is negligible and does not necessarily justify a change in the therapeutic approach to infertility or sperm cryopreservation.

A familial study of azoospermic men identifies three novel causative mutations in three new human azoospermia genes.

PURPOSE: Up to 1% of all men experience azoospermia, a condition of complete absence of sperm in the semen. The mechanisms and genes involved in spermatogenesis are mainly studied in model organisms, and their relevance to humans is unclear because human genetic studies are very scarce. Our objective was to uncover novel human mutations and genes causing azoospermia due to testicular meiotic maturation arrest. METHODS: Affected and unaffected siblings from three families were subjected to whole-exome or whole-genome sequencing, followed by comprehensive bioinformatics analyses to identify mutations suspected to cause azoospermia. These likely mutations were further screened in azoospermic and normozoospermic men and in men proven to be fertile, as well as in a reference database of local populations. RESULTS: We identified three novel likely causative mutations of azoospermia in three genes: MEIOB, TEX14, and DNAH6. These genes are associated with different meiotic processes: meiotic crossovers, daughter cell abscission, and possibly rapid prophase movements. CONCLUSION: The genes and pathways we identified are fundamental for delineating common causes of azoospermia originating in mutations affecting diverse meiotic processes and have great potential for accelerating approaches to diagnose, treat, and prevent infertility.Genet Med advance online publication 16 February 2017.

Distinctive pattern of expression of spermatogenic molecular markers in testes of azoospermic men with non-mosaic Klinefelter syndrome.

PURPOSE: Mature sperm cells can be found in testicular specimens extracted from azoospermic men with non-mosaic Klinefelter syndrome (KS). The present study evaluates the expression of various known molecular markers of spermatogenesis in a population of men with KS and assesses the ability of those markers to predict spermatogenesis. METHODS: Two groups of men with non-obstructive azoospermia who underwent testicular sperm-retrieval procedures were included in the study: 31 had non-mosaic KS (KS group) and 91 had normal karyotype (NK group). Each group was subdivided into mixed atrophy (containing some mature sperm cells) or Sertoli cell only syndrome according to testicular histology and cytology observations. Semi-quantitative histological morphometric analysis (interstitial hyperplasia and hyalinization, tubules with cells and abnormal thickness of the basement membrane) and expression of spermatogenetic markers (DAZ, RBM, BOLL, and CDY1) were evaluated and compared among those subgroups. RESULTS: Clear differences in the histological morphometry and spermatogenetic marker expression were noted between the KS and NK groups. There was a significant difference in the expression of spermatogenetic markers between the subgroups of the NK group (as expected), while no difference could be discerned between the two subgroups in the KS group. CONCLUSION: We conclude that molecular spermatogenetic markers have a pattern of expression in men with KS that is distinctively different from that of men with NK, and that it precludes and limits their use for predicting spermatogenesis in the former. It is suggested that this difference might be due to the specific highly abnormal histological morphometric parameters in KS specimens.

Long-term cryostorage of sperm in a human sperm bank does not damage progressive motility concentration.

BACKGROUND: The use of quarantined cryopreserved semen is mandatory in donor insemination programs. Whether sperm cells can survive and retain their ability to fertilize after long-term storage remains a controversial issue. The objective of this study was to determine the effect of the duration of cryostorage in liquid nitrogen on the sperm cells' progressive motility concentration (PMC) in a large study group. METHODS: A total of 2525 thawed sperm specimens, packed in straws and donated by 72 sperm bank donors for intrauterine insemination (IUI), were evaluated in an assisted reproduction institute. PMC was recorded after 0.5-14.4 years of cryostorage. RESULTS: The mean (+/-SD) value of PMC of all study samples was 10.8 +/- 3.3 x 10(6)/ml after freezing/thawing and before cryostorage (T0), and 12.3 +/- 2.9 x 10(6)/ml after storage and before using the specimen for IUI (T1, P < 0.0001). Specimen storage for different lengths of time revealed that storage duration had no significant influence on the PMC of the specimens (r = -0.03, P = 0.08). The PMC of partially filled straws was lower than in full straws. Cryostorage duration made no difference in the PMC of raw and washed sperm specimens. CONCLUSION: Prolonged storage of donated sperm in liquid nitrogen had no influence on the PMC of the specimens and therefore should not alter the fertilization potency of donated sperm. The high post-storage values of the PMC compared with the pre-storage PMC values was probably an artifact of the small volume of the pre-storage sample.

[The involvement of the zona pellucida in unexplained infertile women].

Unexplained infertility (*UI) was a common problem before the IVF era. A couple was declared as UI only after they passed all the routine common tests and no reason was found for the infertility. The introduction of ICSI in the IVF clinics enabled the investigation of the quality of the couple's gametes. Thus, the definition of the term UI was refined and the number of couples encompassed by this term decreased dramatically. Zona Pellucida (ZP) incompetence was described as one of the causes of UI. We recently (2004) published a case study of an UI couple due to this cause. The oocytes of the woman collapsed during the preparation of the oocytes for sperm injection. These oocytes suffered from irregular ZP and abnormal appearance. Only after gentle treatment of the oocyte-cumulus complex and ICSI fertilization, embryo development and delivery of normal newborn was achieved. This woman and others who suffer from UI did not conceive in a natural way since the ZP of the ovulated eggs did not bind sperm cells and, thereby, were not fertilized. It only recently became possible to find the reason for the infertility of the couple and the solution, through the use of highly advanced technology in the IVF-ICSI process. One of the reasons for the deformatted ZP is the malfunction of the gene that encodes the 4 glycoproteins, which compose the ZP. This is now under investigation in our Institute.

Comparison of efficacy of two techniques for testicular sperm retrieval in nonobstructive azoospermia: multifocal testicular sperm extraction versus multifocal testicular sperm aspiration.

To compare the efficacy of 2 sperm-retrieval procedures, testicular sperm extraction (TESE) and testicular sperm aspiration (TESA), during the same procedure using the same subjects as their own controls. The presence of mature testicular sperm cells and motility were evaluated in 87 men with nonobstructive azoospermia (NOA) by means of multifocal TESE and multifocal TESA, which were performed during the same procedure using the same subjects as their own controls. Sperm cells were recovered by TESE in 54 cases, but by TESA in only 36 cases. There were significantly more cases (n = 20) in which sperm cells were recovered by TESE only, compared with 2 cases in whom cells were recovered by TESA only (McNemar's test, P < .001). The mean number of locations in each testis in which sperm cells were detected was significantly higher in the TESE group. In significantly more cases (n = 27), motility was observed in TESE material only, compared with 3 cases in which motility was present in material extracted by TESA only (McNemar's test, P < .001). Mean number of locations in each testis with motile sperm cells was significantly higher in the TESE group. The TESE procedure yielded significantly more sperm cells, as was also reflected by the difference in number of straws with cryopreserved sperm. This comparative prospective clinical study revealed that multifocal TESE is more efficient than multifocal TESA for sperm detection and recovery in men with NOA and should be the procedure of choice for sperm retrieval for them.

New insights into the role of the Brdt protein in the regulation of development and spermatogenesis in the mouse.

The bromodomain testis-specific (BRDT) protein belongs to the bromodomain extra-terminal (BET) family of proteins. It serves as a transcriptional regulator of gene expression during spermatogenesis, and is an essential factor for the normal spermatogenesis process. In this study, we characterized mice of several age groups who lacked the Brdt gene. The testes of Brdt mutant mice aged 8 weeks exhibited complete spermatocyte maturation arrest with a significantly increased number of apoptotic cells. The weights of the testes and accessory glands as well as the testosterone levels of the mutant mice were significantly lower compared to the normal mice. The mutant mice had delayed puberty, with normal levels of testosterone and accessory gland weights at the age of 14 and 28 weeks. The testes of the mutant mice at older ages also exhibited round spermatids. The presence of the BRDT protein was identified in the mice pituitary gland. Microarray analysis of mice pituitaries showed that 28 genes were down-regulated while 26 genes were up-regulated in the absence of the Brdt gene. Our results suggest that in addition to its critical role in the spermatogenesis process, the BRDT protein is also responsible for scheduling male puberty by regulation of the pituitary-gonad axis.

Severe hypospermatogenesis in cases of nonobstructive azoospermia: should we use fresh or frozen testicular spermatozoa?

The aim of this comparative clinical study was to examine whether the fertilizing potential of frozen-thawed testicular sperm in the most severe cases of hypospermatogenesis is reduced compared with fresh testicular sperm. The results could determine the necessity of using fresh testicular sperm cells, which mandates involving the spouse by performing simultaneous in vitro fertilization intracytoplasmic sperm injection (IVF-ICSI) treatment in this subgroup of nonobstructive azoospermia (NOA) patients. We studied 13 couples in which the husband was diagnosed as having NOA and few motile testicular sperm cells or only immotile testicular sperm cells were isolated by testicular sperm extraction (TESE). Each couple underwent both an ICSI cycle, in which fresh testicular sperm that were retrieved shortly beforehand were injected, and a consecutive cycle, which used frozen-thawed sperm that were retrieved in the original TESE procedure but were cryopreserved and stored until use. We found that motility was lost during the freezing and thawing process in some cases, which resulted in significantly more cycles with only immotile sperm cells for injection in the frozen-thawed sperm group (38.5%) than in the fresh sperm group (7.7%; P < .05). Availability of only immotile sperm cells significantly reduced fertilization rates in both fresh and frozen-thawed groups, but the respective overall fertilization rate (44.9% vs 41.1%) and quality of embryos and pregnancy rate (18.2% vs 15.4%) were not significantly different between groups. Implantation rates were more favorable in the fresh sperm group (10.5% vs 5.9%), but not significantly so. We conclude that, although cryopreservation does impair motility, which results in significantly more cycles with only immotile sperm cells for ICSI in the most severe forms of hypospermatogenesis, fertilization and pregnancy rates are not significantly compromised.

Detection of calretinin expression in abnormal immature Sertoli cells in non-obstructive azoospermia.

The current study identified for the first time calretinin expression in abnormal Sertoli cells of azoospermic men who underwent testicular biopsy for sperm recovery and application of the retrieved sperm by in vitro fertilization techniques. Testicular biopsies with various spermatogenic impairments were evaluated immunohistochemically for the expression of the calretinin calcium-binding protein and the marker for immaturity of Sertoli cells, cytokeratin-18 (CK-18). Distribution of the markers was assessed in testes demonstrating a histological phenotype of mixed atrophy, Sertoli cell-only, or normal spermatogenesis (obstructive-azoospermia) and in men carrying a deletion in the azoospermia factor region located on the Y chromosome. Calretinin-immunopositive immature Sertoli cells revealed by co-localization of both markers, calretinin and CK-18, were identified in the mixed atrophy group in seminiferous tubules demonstrating spermatogenic failure. Sertoli cells expressing both markers were rarely detected in all other groups. Leydig cells in all the assessed biopsies expressed calretinin and served as a built-in control for immunoreactivity. This pattern of calretinin-selective expression in immature Sertoli cells suggests a functional relationship between calretinin expression and the degree of Sertoli cell differentiation. Disorders of Sertoli cell differentiation as indicated by calretinin and/or CK-18 expression contribute to the multifactorial mechanisms underlying spermatogenic failure.

A new power Doppler ultrasound guiding technique for improved testicular sperm extraction.

OBJECTIVE: To develop a noninvasive procedure that employs image processing of power Doppler ultrasound (PDUS) images of several orthogonal cross-sections of the testis to construct a three-dimensional (3D) mapping of preferential testicular regions in which spermatozoa are most likely to be found in nonobstructive azoospermic testes. DESIGN: Clinical study. SETTING: Ultrasound and andrology units in a large university-affiliated municipal hospital. PATIENT(S): Twenty-four nonobstructive azoospermic men. INTERVENTION(S): Before testicular sperm extraction was performed, PDUS images were acquired at seven cross-sections to reconstruct a 3D testicular vascularity index (TVI) matrix for spatial mapping of testicular regions in which spermatozoa are most likely to be found. The predictions based on TVI values of 107 regions were compared with the biopsy results. MAIN OUTCOME MEASURE(S): Prediction of presence or absence of spermatozoa by TVI values. RESULT(S): The prediction rate of the TVI matrix for the presence or absence of spermatozoa was 74.8%. The positive predicted value was 72%, negative predicted value was 75.6%, and specificity was 89.8%, but sensitivity was 47.3%. CONCLUSION(S): Our technique may obviate the need for arbitrary multiple biopsies that inflict some degree of damage upon testicular tissue and may increase the success rate of identifying viable spermatozoa in testicular tissue.

Sertoli cell inactivation by cytotoxic damage to the human testis after cancer chemotherapy.

OBJECTIVE: To assess Sertoli cell involvement in postchemotherapy azoospermia. DESIGN: Case report. SETTING: Teaching hospital. PATIENT(S): A 31-year-old azoospermic man who underwent cancer cytotoxic chemotherapy for non-Hodgkin's lymphoma at 13 years of age. INTERVENTION(S): Testicular biopsy specimens were obtained for sperm recovery in preparation for intracytoplasmic sperm injection. The biopsy specimens were evaluated by quantitative immunohistochemistry for the immature Sertoli cell markers cytokeratin 18 (CK-18) and D2-40. MAIN OUTCOME MEASURE(S): Extent of immature Sertoli cells. RESULT(S): A fraction of Sertoli cells (13%) in the atrophic tubules of this patient reexpressed the intermediate filament protein CK-18, which is normally absent after puberty, but not the D2-40 antigen, an Mr 40,000 a-linked membrane glycoprotein, whose loss of expression at puberty marks an irreversible step in Sertoli cell maturation. Tubules with normal spermatogenic progression lined by Sertoli cells negative for CK-18 were also observed. CONCLUSION(S): A fraction of Sertoli cells of this patient initially progressed to full maturation at puberty and reverted to a dedifferentiated state marked by reexpression of CK-18 as a consequence of chemotherapy. This inactivation of Sertoli cells caused by the cytotoxicity of the chemotherapeutic drugs may have contributed to the spermatogenic impairment and resulting infertility.

Sertoli cell maturation in men with azoospermia of different etiologies.

OBJECTIVE: To evaluate the involvement of Sertoli cell in different spermatogenic disorders. DESIGN: Retrospective case-control study. SETTING: Teaching hospital. PATIENT(S): Azoospermic men who underwent testicular biopsy for sperm recovery in preparation for intracytoplasmic sperm injection. INTERVENTION(S): Testicular biopsy evaluation by quantitative immunohistochemistry for the immature Sertoli cell markers anti-Müllerian hormone and cytokeratin 18 (CK-18). MAIN OUTCOME MEASURE(S): Relative area of immature Sertoli cells in testes with focal spermatogenesis, spermatocyte maturation arrest, or normal spermatogenesis. RESULT(S): The relative area occupied by immature Sertoli cells, as revealed by anti-Müllerian hormone and CK-18 expression, was highest in the 11 men with focal spermatogenesis. In the group representing normal spermatogenesis (obstructive azoospermia, 6 men) and in the group characterized by spermatocyte maturation arrest (6 men), the areas occupied by anti-Müllerian hormone- and CK-18-positive cells were minimal. CONCLUSION(S): Different etiologies underlie the spermatogenic disorders reported in this study. In focal spermatogenesis with high anti-Müllerian hormone and CK-18 expression, the spermatogenic impairment is associated with the presence of immature Sertoli cells. The detection of normal mature Sertoli cells in the spermatocyte maturation arrest group indicates that the spermatogenic defect that is accompanied by an impairment of meiosis is intrinsic to the germ line without affecting Sertoli cell differentiation.

Spermatogonial proliferation patterns in men with azoospermia of different etiologies.

OBJECTIVE: To demonstrate the pattern(s) of spermatogonial proliferation in different spermatogenic disorders. DESIGN: Retrospective case-control study. Teaching hospital. PATIENT(S): Azoospermic men who underwent testicular biopsy for sperm recovery and preparation for intracytoplasmic sperm injection. INTERVENTION(S): Testicular biopsy evaluation by quantitative immunohistochemistry for proliferating cell nuclear antigen (PCNA). MAIN OUTCOME MEASURE(S): The expression of PCNA in spermatogonia as an index of proliferating activity in testes with focal spermatogenesis, spermatocyte maturation arrest, or normal spermatogenesis. RESULT(S): In biopsies with focal spermatogenesis (11 men), there was a statistically significant reduction of PCNA-labeled spermatogonia in seminiferous tubules showing spermatocyte arrest compared with the expression in adjacent tubules with advanced spermatogenic stage or in normal spermatogenesis (obstructive azoospermia, six men). However, PCNA expression in tubules of the group with complete maturation arrest (six men) was significantly higher compared with the same spermatogenic defect-spermatocyte arrest-within focal spermatogenesis biopsies. CONCLUSION(S): Different causes underlie the spermatogenic disorders reported in this study. In focal spermatogenesis, the disorder is associated with the presence of mitotic inactive spermatogonia. The detection of normal active spermatogonia in the spermatocyte arrest group indicates that the spermatogenic defect, which is accompanied by meiosis impairment, is not related to a malfunction of spermatogonial proliferation.

Sex chromosome alignment at meiosis of azoospermic men with azoospermia factor microdeletion.

Deletions in the q arm of the Y chromosome result in spermatogenesis impairment. The aim of the present study was to observe the X and Y chromosome alignment in the spermatocytes of men with Y chromosome microdeletion of the azoospermia factor (AZF) region. This was performed by multicolor fluorescence in situ hybridization probes for the centromere and telomere regions. Testicular biopsies were performed in a testicular sperm extraction-intracytoplasmic sperm injection set-up in 11 azoospermic men: 8 (nonobstructive) with AZF deletions and 3 (obstructive) controls. Histological sections, cytology preparations of the testicular biopsies, and evaluation of the meiosis according to the percentage of XY and 18 bivalents formation were assessed. Spermatozoa were identified in at least one location in controls and specimens with AZFc-deleted Y chromosomes. Complete spermatocyte arrest was found in those with a deletion that included the entire AZFb region. Bivalent formation rate of chromosome 18 was high in all samples (81%-99%). In contrast, the rate of bivalent X-Y as determined by centromeric probes was lower but in the range favorable with spermatozoa findings in controls and patients with the AZFc deletion (56%-90%), but not in those with AZFb-c deletions (28%-29%). A dramatic impairment in the normal alignment of X and Y telomeres in the specimen with AZFb-c deletion was shown (29%), compared to the specimens with AZFc deletion (70%-94%). It is suggested that the absence of sperm cells in specimens with the entire AZFb and with AZFb-c deletions is accompanied by meiosis impairment, perhaps as a result of the extent of the deletion or because of the absence of genes that are involved in the X and Y chromosome alignment.

Lack of RBM expression as a marker for carcinoma in situ of prepubertal dysgenetic testis.

Individuals with various intersex states who carry Y-chromosome material bear a high risk of developing testicular neoplasia. In order to gain more insight into the pathogenesis of this neoplasia, the current study evaluates the differentiation of the seminiferous epithelium in 46,XY dysgenetic male pseudohermaphroditism. Immunohistochemical evaluation was performed using the germ cell-specific RNA-binding motif (RBM) protein (encoded by the Y-chromosome) to identify normal germ cells, whereas placental alkaline phosphatase (PLAP) was used to detect neoplastic germ cells. Differentiation of somatic Sertoli cells was assessed using cytokeratin-18 (CK-18) and anti-Müllerian hormone (AMH) as markers for immature Sertoli cells. Specimens were taken from surgically removed dysgenetic gonads of five children (46XY karyotype). Intratubular germ cell neoplasia (carcinoma in situ [CIS] of the testis) was detected in all of them. Normal germ cells revealed immunoreactivity for RBM, whereas the PLAP-positive neoplastic germ cells were negative for RBM expression. Sertoli cells revealed an immature phenotype indicated by AMH expression in their cytoplasm. The design of the current study is unique in its assessment of the state of germ cell differentiation in dysgenetic gonads by the use of the RBM protein, which was expressed only in normal germ cells but not in those of CIS. Testicular dysgenesis interrupted the normal differentiation of the germ line and had no effect on the immature phenotype of the prepubertal Sertoli cells. This points toward the germinal component of CIS as the precursor for the promotion of testis cancer.

Reduced human germ cell-less (HGCL) expression in azoospermic men with severe germinal cell impairment.

Germ cell-less (GCL) protein is a nuclear envelope protein highly conserved between the mammalian and Drosophila orthologues. In Drosophila, maternal GCL protein is required to establish the germ lineage during embryonic development. In mammals, it is suggested that the GCL function is mainly in spermatogenesis and that it might be related to the ability of mouse GCL to repress transcription. Using reverse transcriptase-polymerase chain reaction analyses, we investigated the role of human GCL (HGCL) in spermatogenesis by studying its expression in the testicular tissue of 67 azoospermic men with normal karyotype and no Y-chromosome microdeletion. Their testicular biopsy specimens underwent meticulous histological and cytological analysis as well as molecular analysis with various markers of spermatogenesis (RBM1, DAZ, and CDY1). The rate of X-Y and 18 chromosome bivalent formation during meiosis was additionally assessed in 22 of these biopsy specimens and correlated to HGCL expression. Expression of HGCL was affected in parallel with the severity of testicular impairment found. Defective sperm motility was associated with the absence of HGCL. Nevertheless, the absence of HGCL expression did not influence the normal process of chromosome bivalent formation in meiosis. Our results suggest that HGCL is not essential for the chromosomal events of meiosis but might be involved in later aspects of spermatogenesis.

Localization of the germ cell-specific protein, hnRNP G-T, in testicular biopsies of azoospermic men.

The increasing interest in the application of in vitro fertilization techniques in human reproduction has led to a wide use of testicular biopsies to identify the presence of spermatogenic foci in testes of azoospermic men. Histopathologic evaluation of these testicular biopsies is required to determine the spermatogenic state with respect to fertility potential and to rule out preinvasive testicular lesions. Heterogeneous nuclear ribonucleoprotein G-T (hnRNP G-T) is a germ cell-specific protein expressed most prominently during meiosis. We studied the usefulness of hnRNP G-T antibody in the evaluation of these biopsies and reasoned that its germ cell-restricted expression pattern might provide a marker to improve accuracy of diagnosis. Testicular biopsies with various spermatogenic impairments were evaluated immunohistochemically for hnRNP G-T expression. In biopsies exhibiting normal spermatogenesis (obstructive azoospermia), hnRNP G-T was localized in meiotic pachytene spermatocytes and round spermatids. Immunostaining was barely detected when maturation was arrested at the spermatocyte level and not at all in cases of Sertoli cell-only syndrome. Biopsies with a mixed histologic phenotype and minute concentrations of spermatogenesis demonstrated strong immunostaining only in tubules with full spermatogenesis. This distribution pattern of hnRNP G-T enabled instant identification of spermatogenic foci. Thus, exploitation of the hnRNP G-T marker, which is expressed preferentially as meiosis proceeds, enhances sensitivity and accuracy of diagnosis in the histologic evaluation of testicular biopsies.

Double immunolabeling by the RBM and the PLAP markers for identifying intratubular (in situ) germ cell neoplasia of the testis.

Identification of intratubular germ cell neoplasia (carcinoma in situ, CIS) of the testis is a diagnostic challenge, and markers are sorely needed to assist in accurately identifying the lesion. RNA-binding motif (RBM) protein, encoded by the Y chromosome, is expressed exclusively and consistently in differentiated male germ cells, while it is absent in neoplastic germ cells. Another immunohistochemical marker, placental alkaline phosphatase (PLAP), is commonly used for the detection of undifferentiated germ cells. The current study demonstrates that simultaneous use of the immunohistochemical markers, RBM and PLAP, by double immunolabeling enhances the accuracy of diagnosing CIS, a preinvasive testicular neoplasm.

[The evaluation of severe male infertility in the era of advanced in-vitro fertilization].

Male infertility has been a subject for dynamic definition during the last decade since the introduction of intracytoplasmic sperm injection (ICSI) as an acceptable and routine technique in the IVF-ART procedure. Male sterility may be defined in cases in which no spermatozoa are located in a testicular biopsy using several specimens. The extreme case (absence of all gametes precursors) is termed Sertoli cell only. This evaluation may be reinforced by detailed genetic assessments of micro-deletion in Y chromosome. Accordingly, once spermatozoa are isolated (even very few) they can fertilize an oocyte using ICSI, thereby the couple can achieve pregnancy. This shift in the definition of 'Sterility' brings about a shift in the consideration of male 'subfertility' or 'infertility'. This review explores the current 'state of the art' of male fertility evaluation with a focus on the role of an advanced andrology laboratory.

[The prognostic value of the site and extent of Y chromosome microdeletions on spermatogenesis].

Genes on Y-chromosome are involved in the regulation of spermatogenesis. Y-chromosome microdeletions were identified among infertile patients in a frequency of 7.5-15% on the long arm of the chromosome. These microdeletions were clustered in 3 main regions named AZFa, AZFb, and AZFc. Reanalyzing the histological findings in men with well-defined varying extent of Y-chromosome microdeletions improved our understanding of the prospect of finding testicular spermatozoa. The chances of finding spermatozoa were almost nil in men with microdeletions that include the complete AZFa region or AZFb region or at least two AZF regions. Large microdeletions that include the Yq tip were suggested to cause chromosomal instability and were shown to be prone to Y chromosome loss. In addition, a decrease of sperm count over time in men with AZFc deletions has been reported and the option of spermatozoa cryo-preservation need to be taken in consideration. Analysis of the Y-chromosome microdeletion was found to be of prognostic value in cases of infertility both in terms of clinical management as well as for understanding the etiology of the spermatogenesis impairment.