Progesterone levels do not differ between patients with or without endometriosis/adenomyosis both in those who conceive after hormone replacement therapy-frozen embryo transfer cycles and those who do not.

STUDY QUESTION: Do women with endometriosis who achieve a live birth (LB) after HRT-frozen embryo transfer (HRT-FET) have different progesterone levels on the day of transfer compared to unaffected women? SUMMARY ANSWER: In women achieving a LB after HRT-FET, serum progesterone levels on the day of the transfer did not differ between patients with endometriosis and unaffected patients. WHAT IS KNOWN ALREADY: In HRT-FET, several studies have highlighted the correlation between serum progesterone levels at the time of FET and LB rates. In the pathophysiology of endometriosis, progesterone resistance is typically described in the eutopic endometrium. This has led to the hypothesis that women with endometriosis may require higher progesterone levels to achieve a LB, especially in HRT-FET cycles without a corpus luteum. STUDY DESIGN, SIZE, DURATION: We conducted an observational cohort study at the university-based reproductive medicine center of our institution, focusing on women who underwent a single autologous frozen blastocyst transfer after HRT using exogenous estradiol and micronized vaginal progesterone for endometrial preparation between January 2019 and December 2021. Women were included only once during the study period. Serum progesterone levels were measured on the morning of the FET by a single laboratory. PARTICIPANTS/MATERIALS, SETTING, METHODS: Patients were divided into groups based on whether they had endometriosis or not and whether they achieved a LB. The diagnosis of endometriosis was based on published imaging criteria (transvaginal sonography/magnetic resonance imaging) and/or confirmed histology. The primary outcome was progesterone levels on the day of the HRT-FET leading to a LB in patients with endometriosis compared to unaffected women. Subgroup analyses were performed based on the presence of deep infiltrating endometriosis or adenomyosis. MAIN RESULTS AND THE ROLE OF CHANCE: A total of 1784 patients were included. The mean age of the women was 35.1 ± 4.1 (SD) years. Five hundred and sixty women had endometriosis, while 1224 did not. About 179/560 (32.0%) with endometriosis and 381/1224 (31.2%) without endometriosis achieved a LB. Among women who achieved a LB after HRT-FET, there was no significant difference in the mean progesterone level on the day of the HRT-FET between those with endometriosis and those without (13.6 ± 4.3 ng/ml vs 13.2 ± 4.4 ng/ml, respectively; P = 0.302). In the subgroup of women with deep infiltrating endometriosis (n = 142) and adenomyosis (n = 100), the mean progesterone level was 13.1 ± 4.1 ng/ml and 12.6 ± 3.7 ng/ml, respectively, with no significant difference compared to endometriosis-free patients. After adjusting for BMI, parity, duration of infertility, tobacco use, and geographic origin, neither the presence of endometriosis (coefficient 0.38; 95% CI: -0.63 to 1.40; P = 0.457) nor the presence of adenomyosis (coefficient 0.97; 95% CI: -0.24 to 2.19; P = 0.114) was associated with the progesterone level on the day of HRT-FET. Among women who did not conceive, there was no significant difference in the mean progesterone level on the day of the HRT-FET between those with endometriosis and those without (P = 0.709). LIMITATIONS, REASONS FOR CAUTION: The primary limitation of our study is associated with its observational design. Extrapolating our results to other laboratories or different routes and/or dosages of administering progesterone also requires validation. WIDER IMPLICATIONS OF THE FINDINGS: This study shows that patients diagnosed with endometriosis do not require higher progesterone levels on the day of a frozen blastocyst transfer to achieve a LB in hormonal replacement therapy cycles. STUDY FUNDING/COMPETING INTEREST(S): None declared. TRIAL REGISTRATION NUMBER: N/A.

Intra-individual variability of serum progesterone levels on the day of frozen blastocyst transfer in hormonal replacement therapy cycles.

STUDY QUESTION: Is there a significant intra-individual variability of serum progesterone levels on the day of single blastocyst Hormone Replacement Therapy-Frozen Embryo Transfer (HRT-FET) between two consecutive cycles? SUMMARY ANSWER: No significant intra-individual variability of serum progesterone (P) levels was noted between two consecutive HRT-FET cycles. WHAT IS KNOWN ALREADY: In HRT-FET cycles, a minimum P level on the day of embryo transfer is necessary to optimise reproductive outcomes. In a previous study by our team, a threshold of 9.8 ng/ml serum P was identified as significantly associated with the live birth rates in single autologous blastocyst transfers under HRT using micronized vaginal progesterone (MVP). Such patients may benefit from an intensive luteal phase support (LPS) using other routes of P administration in addition to MVP. A crucial question in the way towards individualising LPS is whether serum P measurements are reproducible for a given patient in consecutive HRT-FET cycles, using the same LPS. STUDY DESIGN, SIZE, DURATION: We conducted an observational cohort study at the university-based reproductive medicine centre of our institution focusing on women who underwent at least two consecutive single autologous blastocyst HRT-FET cycles between January 2019 and March 2020. PARTICIPANTS/MATERIALS, SETTING, METHODS: Patients undergoing two consecutive single autologous blastocyst HRT-FET cycles using exogenous oestradiol and vaginal micronized progesterone for endometrial preparation were included. Serum progesterone levels were measured on the morning of the Frozen Embryo Transfer (FET), by a single laboratory. The two measurements of progesterone levels performed on the day of the first (FET1) and the second FET (FET2) were compared to evaluate the intra-individual variability of serum P levels. Paired statistical analyses were performed, as appropriate. MAIN RESULTS AND THE ROLE OF CHANCE: Two hundred and sixty-four patients undergoing two consecutive single autologous blastocyst HRT-FET were included. The mean age of the included women was 35.0 ± 4.2 years. No significant intra-individual variability was observed between FET1 and FET2 (mean progesterone level after FET1: 13.4 ± 5.1 ng/ml vs after FET2: 13.9 ± 5.0; P = 0.08). The characteristics of the embryo transfers were similar between the first and the second FET. Forty-nine patients (18.6%) had discordant progesterone levels (defined as one progesterone measurement > and one ≤ to the threshold of 9.8 ng/ml) between FET1 and FET2. There were 37/264 women (14.0%) who had high intra-individual variability (defined as a difference in serum progesterone values >75th percentile (6.0 ng/ml)) between FET1 and FET2. No specific clinical parameter was associated with a high intra-individual variability nor a discordant P measurement. LIMITATIONS, REASONS FOR CAUTION: This study is limited by its retrospective design. Moreover, only women undergoing autologous blastocyst HRT-FET with MVP were included, thereby limiting the extrapolation of the study findings to other routes of P administration and other kinds of endometrial preparation for FET. WIDER IMPLICATIONS OF THE FINDINGS: No significant intra-individual variability was noted. The serum progesterone level appeared to be reproducible in >80% of cases. These findings suggest that the serum progesterone level measured on the day of the first transfer can be used to individualize luteal phase support in subsequent cycles. STUDY FUNDING/COMPETING INTEREST(S): No funding or competing interests. TRIAL REGISTRATION NUMBER: N/A.

Endometriosis-related infertility: severe pain symptoms do not impact assisted reproductive technology outcomes.

STUDY QUESTION: Do severe endometriosis-related painful symptoms impact ART live birth rates? SUMMARY ANSWER: Severe pain symptoms are not associated with reduced ART live birth rates in endometriosis patients. WHAT IS KNOWN ALREADY: ART is currently recognized as one of the main therapeutic options to manage endometriosis-related infertility. Presently, no data exist in the literature regarding the association between the core symptom of the disease, e.g. pain and ART reproductive outcomes. STUDY DESIGN, SIZE, DURATION: Observational cohort study of 354 endometriosis patients, who underwent ART at a tertiary care university hospital, between October 2014 and October 2021. Diagnosis of endometriosis was based on published imaging criteria using transvaginal sonography and magnetic resonance imaging, and histologically confirmed in women who had a previous history of endometriosis surgery (n = 127, 35.9%). PARTICIPANTS/MATERIALS, SETTING, METHODS: The intensity of painful symptoms related to dysmenorrhea (DM), dyspareunia (DP), noncyclic chronic pelvic pain, gastrointestinal (GI) pain, or lower urinary tract pain was evaluated using a 10-point visual analog scale (VAS), before ART. Severe pain was defined as having a VAS of 7 or higher for at least one symptom. The main outcome measure was the cumulative live birth rate (CLBR) per patient. We analyzed the impact of endometriosis-related painful symptoms on ART live births using univariable and multivariate analysis. MAIN RESULTS AND THE ROLE OF CHANCE: Three hundred and fifty-four endometriosis patients underwent 711 ART cycles. The mean age of the population was 33.8 ± 3.7 years, and the mean duration of infertility was 3.6 ± 2.1 years. The distribution of the endometriosis phenotypes was 3.1% superficial endometriosis, 8.2% ovarian endometrioma, and 88.7% deep infiltrating endometriosis. The mean VAS scores for DM, DP, and GI pain symptoms were 6.6 ± 2.7, 3.4 ± 3.1, and 3.1 ± 3.6, respectively. Two hundred and forty-two patients (68.4%) had severe pain symptoms. The CLBR per patient was 63.8% (226/354). Neither the mean VAS scores for the various painful symptoms nor the proportion of patients displaying severe pain differed significantly between patients who had a live birth and those who had not, based on univariate and multivariate analyses (P = 0.229). The only significant factors associated with negative ART live births were age >35 years (P < 0.001) and anti-Müllerian hormone levels <1.2 ng/ml (P < 0.001). LIMITATIONS, REASONS FOR CAUTION: The diagnosis of endometriosis was based on imaging rather than surgery. This limitation is, however, inherent to the design of most studies on endometriosis patients reverting to ART first. WIDER IMPLICATIONS OF THE FINDINGS: Rather than considering a single argument such as pain, the decision-making process for choosing between ART and surgery in infertile endometriosis patients should be based on a multitude of aspects, including the patient's choice, the associated infertility factors, the endometriosis phenotypes, and the efficiency of medical therapies in regard to pain symptoms, through an individualized approach guided by a multidisciplinary team of experts. STUDY FUNDING/COMPETING INTEREST(S): No funding; no conflict of interest. TRIAL REGISTRATION NUMBER: N/A.

Clinical factors associated with low serum progesterone levels on the day of frozen blastocyst transfer in hormonal replacement therapy cycles.

STUDY QUESTION: Which factors are associated with low serum progesterone (P) levels on the day of frozen embryo transfer (FET), in HRT cycles? SUMMARY ANSWER: BMI, parity and non-European geographic origin are factors associated with low serum P levels on the day of FET in HRT cycles. WHAT IS KNOWN ALREADY: The detrimental impact of low serum P concentrations on HRT-FET outcomes is commonly recognized. However, the factors accounting for P level disparities among patients receiving the same luteal phase support treatment remain to be elucidated, to help clinicians predicting which subgroups of patients would benefit from a tailored P supplementation. STUDY DESIGN, SIZE, DURATION: Observational cohort study with 915 patients undergoing HRT-FET at a tertiary care university hospital, between January 2019 and March 2020. PARTICIPANTS/MATERIALS, SETTING, METHODS: Patients undergoing single autologous blastocyst FET under HRT using exogenous estradiol and vaginal micronized progesterone for endometrial preparation. Women were only included once during the study period. The serum progesterone level was measured in the morning of the FET, in a single laboratory. Independent factors associated with low serum P levels (defined as ≤9.8 ng/ml, according to a previous published study) were analyzed using univariate and multivariate logistic regression models. MAIN RESULTS AND THE ROLE OF CHANCE: Two hundred and twenty-six patients (24.7%) had a low serum P level, on the day of the FET. Patients with a serum P level ≤9.8 ng/ml had a lower live birth rate (26.1% vs 33.2%, P = 0.045) and a higher rate of early miscarriage (35.2% vs 21.5%, P = 0.008). Univariate analysis showed that BMI (P < 0.001), parity (P = 0.001), non-European geographic origin (P = 0.001), the duration of infertility (P = 0.018) and the use of oral estradiol for endometrial preparation (P = 0.009) were significantly associated with low serum P levels. Moreover, the proportion of active smokers was significantly lower in the 'low P concentrations' group (P = 0.002). After multivariate analysis, BMI (odds ratio (OR) 1.06 95% CI (1.02-1.11), P = 0.002), parity (OR 1.32 95% CI (1.04-1.66), P = 0.022), non-European geographic origin (OR 1.70 95% CI (1.21-2.39), P = 0.002) and active smoking (OR 0.43 95% CI (0.22-0.87), P = 0.018) remained independent factors associated with serum P levels ≤9.8 ng/ml. LIMITATIONS, REASONS FOR CAUTION: The main limitation of this study is its observational design, leading to a risk of selection and confusion bias that cannot be ruled out, although a multivariable analysis was performed to minimize this. WIDER IMPLICATIONS OF THE FINDINGS: Extrapolation of our results to other laboratories, or other routes and/or doses of administering progesterone also needs to be validated. There is urgent need for future research on clinical factors affecting P concentrations and the underlying pathophysiological mechanisms, to help clinicians in predicting which subgroups of patients would benefit from individualized luteal phase support. STUDY FUNDING/COMPETING INTEREST(S): No funding/no conflicts of interest. TRIAL REGISTRATION NUMBER: N/A.

[French clinical practice guidelines developed by a modified Delphi consensus process for oocyte vitrification in women with benign gynecologic disease]. / Indications de vitrification ovocytaire dans les pathologies gynécologiques bénignes : conseils de bonne pratique du CNGOF après étude de consensus par méthode Delphi.

OBJECTIVES: To provide clinical practice guidelines about fertility preservation (FP) for women with benign gynecologic disease (BGD) developed by a modified Delphi consensus process for oocyte vitrification in women with benign gynecologic disease. METHODS: A steering committee composed of 14 healthcare professionals and a patient representative with lived experience of endometriosis identified 42 potential practices related to FP for BGD. Then 114 key stakeholders including various healthcare professionals (n=108) and patient representatives (n=6) were asked to participate in a modified Delphi process via two online survey rounds from February to September 2020 and a final meeting. Due to the COVID-19 pandemic, this final meeting to reach consensus was held as a videoconference in November 2020. RESULTS: Survey response of stakeholders was 75 % (86/114) for round 1 and 87 % (75/86) for round 2. Consensus was reached for the recommendations for 28 items, that have been distributed into five general categories: (i) Information to provide to women of reproductive age with a BGD, (ii) Technical aspects of FP for BGD, (iii) Indications for FP in endometriosis, (iv) Indications for FP for non-endometriosis BGD, (v) Indications for FP after a fortuitous diagnosis of an idiopathic diminished ovarian reserve. CONCLUSION: These guidelines provide some practice advice to help health professionals better inform women about the possibilities of cryopreserving their oocytes prior to the management of a BGD that may affect their ovarian reserve and fertility. STUDY FUNDING/COMPETING INTEREST(S): The CNGOF (Collège National des Gynécologues Obstétriciens Français) funded the implementation of the Delphi process.

Xq25 duplication: the crucial role of the STAG2 gene in this novel human cohesinopathy.

The Xq25 duplications syndrome has recently emerged as a distinct clinical entity. We report here on six new patients belonging to two unrelated families and harbouring an Xq25 microduplication detected by array CGH. Similarly to previously reported cases, the phenotype of our patients is characterized by delayed milestones, speech disturbance, intellectual disability, abnormal behaviours and a characteristic facial dysmorphism. The common duplicated interval allowed further refinement of the shortest region of overlap to 173 kb, including only one gene, STAG2, which encodes a component of the cohesin complex. We suggest that increased STAG2 gene copy number and dysregulation of its downstream target genes may be responsible for the specific clinical findings of this syndrome. Therefore, the Xq25 microduplication could be considered as a novel cohesinopathy, thus increasing the group of these disorders.

[An update on adenomyosis and implantation]. / Adénomyose et implantation : mise au point.

Adenomyosis is an enigmatic disease whose impact on implantation and fertility outcome is still controversial. A negative effect on IVF outcome was already observed, but it is mainly explained by an increase in early spontaneous miscarriages. We reviewed scientific data in order to bring relevant information about adenomyosis and endometrial receptivity for patient counselling and to precise if screening of adenomyosis is indicated before IVF treatment.

[Pre-washing catheter dramatically improves the post intrauterine insemination pregnancy rate]. / Le rinçage des cathéters avant insémination intra-utérine augmente considérablement les taux de grossesses.

OBJECTIVE: To analyze the effectiveness of pre-washing the intrauterine insemination catheters on IUI outcome. PATIENTS AND METHODS: Infertile couples (n=322) involved in a IUI program were included in the study. IUI indications were cervical factors, ovulation dysfunction, cryopreserved semen and unexplained infertility. Every other week for two years, IUI catheters were washed with culture medium prior to intrauterine sperm insemination. RESULT(S): Only the first IUI for each couple were analyzed. Washing the catheter, prior to use, resulted in a 49.7% increase in clinical pregnancy rate (22.0% vs 14.7% P<0.05). This result is observed with fresh sperm (15.7% vs 11.1%) and frozen-thawed sperm as well (31.1% vs 19.8%). The early pregnancy termination rate was similar in all groups. DISCUSSION AND CONCLUSION: Pre-washing the catheter before IUI should be recommended in Good Laboratory Practice Guidelines as it is already the case for embryo transfer catheters. This raises the problem of washing all single-use devices, in contact with gametes or embryos during IVF.

[ART with sperm donor after intraconjugal ICSI failure]. / Prise en charge en don de sperme après échec(s) d'ICSI intraconjugale.

OBJECTIVES: To evaluate the ART results with sperm donation for couples who do not succeed after IC ICSI treatment for male infertility. PATIENTS AND METHODS: Retrospective study of 71 couples (November 1994-February 2009). Two control populations were determined to analyse this two-steps treatment (IC and sperm donation) based on different criteria such as the date of ICSI, the female age at the time of the first attempt and the male indication. RESULTS: In IC-ICSI, the proportion of azoospermic subjects and/or carrying chromosomal abnormalities was significantly higher in the studied population as compared to control. The fertilization rate (FR) and the embryo quality were significantly lower in the studied population. After donation, 30 couples (42.2%) succeeded in being parents. The donor IA pregnancy rates were similar to those of the control population except for the azoospermic patients with poor results. When IVF/ICSI-D was performed, the pregnancy rates were lower than in the control population. DISCUSSION AND CONCLUSION: Sperm donation constitutes an option for half of the couples initially treated with IC-ICSI for male infertility. For couples who failed in sperm donation, a female implication cannot be excluded, even though not detected.

[Role of the female environment in sperm capacitation]. / La capacitation in vivo: influence de l'environnement féminin.

The female genital tract plays a vital role in ensuring successful fertilization and normal early embryonic development. The process of capacitation needs an active and specific coordination between the female tract, ovulation and the spermatozoa. During sperm ascension towards the fertilisation site, a final maturation of male gametes, also called sperm capacitation, takes place in a well-controlled manner. Before ovulation, most of spermatozoa bind oviduct, in the isthmic region that plays a role of sperm reservoir. During sperm binding to the epithelial cells the capacitation process is delayed and spermatozoa can survey several days. The capacitation is completed when spermatozoa are released at the ovulation time. They are then guided towards the oocyte likely thanks to combination of female factors, including those provided from oviduct secretions and cumulus cells.

ICSI outcomes in obstructive azoospermia: influence of the origin of surgically retrieved spermatozoa and the cause of obstruction.

BACKGROUND: Spermatozoa can be retrieved from the testis and epididymis of men with obstructive azoospermia (OA) and used for ICSI. However, it is unknown whether the outcome of ICSI depends on the cause of obstruction or the origin of surgically retrieved spermatozoa. METHODS: A cohort of 171 men with OA and normal spermatogenesis were included in this retrospective study. They were divided into three groups according to the site and origin of obstruction: 83 men had congenital bilateral absence of vas deferens; 55 and 33 had acquired epididymal and deferent duct obstructions, respectively. The outcome of 368 ICSI cycles was determined and compared according to the origin of spermatozoa: epididymal (n = 253) or testicular (n = 115). RESULTS: Fertilization and clinical pregnancy rates did not differ between spermatozoa of different origin (58.9% versus 51.9% and 22.1% versus 24.3% with epididymal and testicular spermatozoa, respectively). However, the miscarriage rate was significantly higher for testicular spermatozoa (35.7% versus. 12.5% P < 0.05, chi2 test). Findings were similar whatever the aetiology of the OA. CONCLUSION: This study suggests that the use of testicular spermatozoa, even those generated during normal spermatogenesis, alters embryonic development and that epididymal spermatozoa should be preferentially used, irrespective of the aetiology of OA.

Is the CAG repeat of mitochondrial DNA polymerase gamma (POLG) associated with male infertility? A multi-centre French study.

BACKGROUND: Recent data emphasized the implication of polymerase gamma (POLG) CAG repeats in infertility, making it a very attractive gene for study. A comparison of POLG CAG repeats in infertile and fertile men showed a clear association between the absence of the usual 10-CAG allele and male infertility, excluding azoospermia. It has also been suggested that the POLG gene polymorphism should be considered as a possible contributing factor in unexplained couple infertility where semen parameters are normal. In this study, we investigated the POLG CAG repeats, in a well-defined population of patients with severe male factor infertility. METHODS: We conducted a large study of POLG CAG repeats in 433 infertile and 91 fertile, normozoospermic and healthy males. In all subjects, phenotypic data, including semen parameters, hormonal status and clinical profiles, were available. RESULTS: Thirteen 'homozygous mutants' (3%) were found among the 433 idiopathic infertile patients. The follow-up of the 13 'homozygous mutant' resulted in pregnancy for more than half of the couples, through assisted reproductive techniques or even spontaneously. In addition, one 'homozygous mutant' was identified in 91 fertile men (1.1%) CONCLUSION: Under our conditions, our study does not confirm any relationship between the polymorphic CAG repeat in the POLG gene and male infertility.

[Molecular detection of Y chromosome microdeletions: a new approach based on the denaturing gradient gel electrophoresis]. / Les méthodes de détection des microdélétions du chromosome Y: intérêt d'une nouvelle approche fondée sur la méthode d'électrophorèse en gradient de gel dénaturant.

Ten percent of couples trying for a child fail to conceive. In approximately 50% of cases, infertility is due to the inability of the male partner to produce spermatozoa in sufficient numbers to effect conception. Over the past 5 years, molecular studies have suggested that interstitial microdeletions in Yq11 represent an etiological factor for male infertility. Y-microdeletions have been detected in 12% of non-obstructive azoospermia and 6% of severe oligozoospermia. In general, microdeletions were detected by separate multiplex-polymerase chain reaction (PCR) reactions using primer pairs for single tagged sites (STSs) of all three azoospermia factor (AZF) regions (AZFa, AZFb and AZFc). This review describes the molecular methods and laboratory guidelines for molecular diagnosis of Y-chromosomal microdeletions. The diagnostics of Y-chromosomal microdeletions should be performed in two steps: in any case, the routine diagnostic should include six STS loci, two STS loci localised in each AZF region, and once a deletion is detected, the analysis can be extended to STS loci known to cross the proximal and the distal borderlines of each AZF region. Other molecular techniques such as DGGE, Southern blot should be performed to detect partial deletions of gene copies or mosaicism. These different molecular approaches should allow explaining 10% of male infertility, to evaluate the risk to pass the defect onto their male offspring (by intracytoplasmic sperm injection) and improve the genetic counselling of couples undergoing micromanipulative assisted reproduction.

[Indications and modalities of assisted reproductive techniques in infertile women with cystic fibrosis]. / Mucoviscidose féminine et projet d'enfant: spécificités des indications et résultats de l'aide médicale à la procréation.

OBJECTIVE: To treat cystic fibrosis women who failed to conceive. PATIENTS AND METHODS: Multidisciplinary coordinated approach in 20 infertile women affected with cystic fibrosis. Advisability of pregnancy was based on the assessment of pulmonary and nutritional status, risks of maternal health deterioration, infertility factors, risk of cystic fibrosis in the offspring. Assisted reproductive techniques in moderately affected women are described. RESULTS: Three patients requested only information, three were discouraged, two are still evaluated, 12 were treated and three delivered healthy children. The pulmonary status of each patient remained unchanged 36 months after delivery, and all three children remain healthy. DISCUSSION AND CONCLUSION: Assisted reproductive techniques are an option in moderately affected infertile cystic fibrosis women. Advisability and management of pregnancy should be provided by a coordinated team of healthcare professionals with knowledge and experience in cystic fibrosis.

[Male infertility and microdeletions of the Y chromosome]. / Infertilité masculine et les microdélétions du chromosome Y.

It is estimated that about 10% of men suffer from male infertility. Male infertility is associated with a reduction in the quantity, reduced mobility or abnormal morphology of sperm. In about 50-60% of cases the etiology can be identified. When the cause is unknown, it is referred to as idiopathic infertility. A genetic cause is suspected in some of the latter cases since chromosome anomalies and familial forms of male infertility have been reported. Three different regions of the Y chromosome, termed AZFa, AZFb and AZFc are recurrently deleted in about 15% of cases of idiopathic azoospermia or severe oilgozoospermia. AZFc deletions form the majority of these deletions. The presence of a Y microdeletion does not seem to alter the fertilisation of the oocyte or the development of the embryo. However, if the child is a boy, he will inherit the deletion from his father and will most likely be infertile when he is an adult. In the absence of any other information concerning an association between Y chromosome microdeletions and other development anomalies of the child, in genetic counselling the principal risk for male offspring appears to be infertility.

Progesterone induces hyperpolarization after a transient depolarization phase in human spermatozoa.

Progesterone (P4) induces a membrane depolarization and various ion fluxes (chloride efflux, sodium and calcium influxes), which are required for the human sperm acrosome reaction (AR). By use of the potentiometric fluorescent dye DiSC3(5) and two different technical approaches, the present study aimed to quantify and further analyze P4-induced modifications in membrane potential in capacitated human spermatozoa. Spectrofluorimetric analysis revealed that the mean resting membrane potential of sperm was -58 +/- 2 mV (n = 12). When 10 microM P4 was added, the sperm membrane depolarized by approximately +15 mV, partly driven by a Cl- efflux. It subsequently repolarized to reach a significant lower potential than the initial resting potential in two thirds of the tested samples. The flow cytometry analysis showed a heterogeneous resting membrane potential and revealed that the depolarization-hyperpolarization events concerned only subpopulations, between 3% and 40% of the sperm cells according to the samples (n = 7). We hypothesize that P4 has a beneficial effect on the ability of zona pellucida to promote the AR in a sperm subpopulation by increasing the number of hyperpolarized cells presenting a membrane potential that is compatible with the opening of T-type calcium channels by subsequent zona pellucida-induced depolarization.

Reduction in the DAZ gene copy number in two infertile men with impaired spermatogenesis.

Microdeletions of Yq are associated with azoospermia and severe oligozoospermia. Recently, we described a new molecular genetic strategy based on the denaturing gradient gel electrophoresis (DGGE) to rapidly identify deletions of the Y chromosome that include the DAZ locus. Using this approach, we have shown not a complete deletion but only a reduction in the number of copies of the DAZ gene by PCR-DGGE in two oligozoospermic patients. These results have been confirmed by Southern blot analysis. This finding suggests that partial deletion of the DAZ cluster could be cause of impaired spermatogenesis.

The acrosome reaction in human spermatozoa.

During gamete interaction, sperm acrosome reaction (AR) induced by oocyte investment is a prerequisite event for the spermatozoa to pass through the zona pellucida (ZP), fuse with and penetrate the oocyte. Progesterone (P4), secreted by cumulus cells, is an important cofactor for the occurrence of this exocytosis event. The AR results from the fusion between outer acrosomal and plasma membranes, leading to inner acrosomal membrane exposure. Binding of agonists, P4 or ZP3 glycoprotein, to plasma membrane sperm receptors activates intraspermatic signals and enzymatic pathways involved in the AR. Among the proteins or glycoproteins described as potential sperm receptors for ZP, Gi/Go protein-coupled and tyrosine kinase receptors have been described. Sperm receptors for P4 are poorly characterized, except a putative GABA(A)-like receptor. ZP- and P4-promoted AR is mediated by an obligatory intracellular calcium increase, appearing first at the acrosome equatorial segment and spreading throughout the head. The plasma membrane channels involved in calcium entry are operated by a plasma membrane depolarization and protein phosphorylations mediated by protein kinase C and tyrosine kinase protein. Part of the calcium increase could also be due to intracellular store release through IP3- and nucleotide (cAMP)-gated channels. Besides adenylate cyclase and phospholipase C activations, intracellular calcium increase also stimulates PLA2 activity and actin depolymerization, leading to membrane fusion. Evaluation of AR by staining or fluorescent probes can be useful to predict fertilization success and to direct the therapeutic strategy in male infertility.