Study of SARS-CoV-2 in semen from asymptomatic donors with the presence of virus in nasopharyngeal swabs.

RESEARCH QUESTION: Is severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) present in semen samples from asymptomatic donors who have positive virus results from nasopharyngeal swabs? DESIGN: Nasopharyngeal PCR was performed on 1943 sperm donors between January 2021 and March 2022. The result was positive for 140 donations, and the presence of SARS-CoV-2 could be studied in cryopreserved semen from 84 of these donors. This included 67 participants in whom the quality of fresh semen could be compared with the previous donation, the day of the PCR-positive nasopharyngeal sampling and the first subsequent donation. Semen donations were cryopreserved following total semen (n = 26) or ready-to-use (n = 58) protocols. The presence of SARS-CoV-2 in cryopreserved samples was determined by reverse transcription PCR. Semen quality (volume, concentration and progressive motility) was evaluated in accordance with World Health Organization 2010 recommendations. RESULTS: SARS-CoV-2 virus was not detected in any cryopreserved total semen or ready-to-use samples. No significant differences in semen volume, concentration or progressive motility were observed between the last previous donation, the day of the positive PCR nasopharyngeal sampling and the first subsequent donation. CONCLUSIONS: The lack of detection of SARS-CoV-2 in semen samples from asymptomatic individuals infected with SARS-CoV-2 supports the safety of assisted human reproduction treatments using this type of sample.

Immune and spermatogenesis-related loci are involved in the development of extreme patterns of male infertility.

We conducted a genome-wide association study in a large population of infertile men due to unexplained spermatogenic failure (SPGF). More than seven million genetic variants were analysed in 1,274 SPGF cases and 1,951 unaffected controls from two independent European cohorts. Two genomic regions were associated with the most severe histological pattern of SPGF, defined by Sertoli cell-only (SCO) phenotype, namely the MHC class II gene HLA-DRB1 (rs1136759, P = 1.32E-08, OR = 1.80) and an upstream locus of VRK1 (rs115054029, P = 4.24E-08, OR = 3.14), which encodes a protein kinase involved in the regulation of spermatogenesis. The SCO-associated rs1136759 allele (G) determines a serine in the position 13 of the HLA-DRß1 molecule located in the antigen-binding pocket. Overall, our data support the notion of unexplained SPGF as a complex trait influenced by common variation in the genome, with the SCO phenotype likely representing an immune-mediated condition.

Common genetic variation in KATNAL1 non-coding regions is involved in the susceptibility to severe phenotypes of male infertility.

BACKGROUND: Previous studies in animal models evidenced that genetic mutations of KATNAL1, resulting in dysfunction of its encoded protein, lead to male infertility through disruption of microtubule remodelling and premature germ cell exfoliation. Subsequent studies in humans also suggested a possible role of KATNAL1 single-nucleotide polymorphisms in the development of male infertility as a consequence of severe spermatogenic failure. OBJECTIVES: The main objective of the present study is to evaluate the effect of the common genetic variation of KATNAL1 in a large and phenotypically well-characterised cohort of infertile men because of severe spermatogenic failure. MATERIALS AND METHODS: A total of 715 infertile men because of severe spermatogenic failure, including 210 severe oligospermia and 505 non-obstructive azoospermia patients, as well as 1058 unaffected controls were genotyped for three KATNAL1 single-nucleotide polymorphism taggers (rs2077011, rs7338931 and rs2149971). Case-control association analyses by logistic regression assuming different models and in silico functional characterisation of risk variants were conducted. RESULTS: Genetic associations were observed between the three analysed taggers and different severe spermatogenic failure groups. However, in all cases, the haplotype model (rs2077011*C | rs7338931*T | rs2149971*A) better explained the observed associations than the three risk alleles independently. This haplotype was associated with non-obstructive azoospermia (adjusted p = 4.96E-02, odds ratio = 2.97), Sertoli-cell only syndrome (adjusted p = 2.83E-02, odds ratio = 5.16) and testicular sperm extraction unsuccessful outcomes (adjusted p = 8.99E-04, odds ratio = 6.13). The in silico analyses indicated that the effect on severe spermatogenic failure predisposition could be because of an alteration of the KATNAL1 splicing pattern. CONCLUSIONS: Specific allelic combinations of KATNAL1 genetic polymorphisms may confer a risk of developing severe male infertility phenotypes by favouring the overrepresentation of a short non-functional transcript isoform in the testis.

Common Variation in the PIN1 Locus Increases the Genetic Risk to Suffer from Sertoli Cell-Only Syndrome.

We aimed to analyze the role of the common genetic variants located in the PIN1 locus, a relevant prolyl isomerase required to control the proliferation of spermatogonial stem cells and the integrity of the blood-testis barrier, in the genetic risk of developing male infertility due to a severe spermatogenic failure (SPGF). Genotyping was performed using TaqMan genotyping assays for three PIN1 taggers (rs2287839, rs2233678 and rs62105751). The study cohort included 715 males diagnosed with SPGF and classified as suffering from non-obstructive azoospermia (NOA, n = 505) or severe oligospermia (SO, n = 210), and 1058 controls from the Iberian Peninsula. The allelic frequency differences between cases and controls were analyzed by the means of logistic regression models. A subtype specific genetic association with the subset of NOA patients classified as suffering from the Sertoli cell-only (SCO) syndrome was observed with the minor alleles showing strong risk effects for this subset (ORaddrs2287839 = 1.85 (1.17-2.93), ORaddrs2233678 = 1.62 (1.11-2.36), ORaddrs62105751 = 1.43 (1.06-1.93)). The causal variants were predicted to affect the binding of key transcription factors and to produce an altered PIN1 gene expression and isoform balance. In conclusion, common non-coding single-nucleotide polymorphisms located in PIN1 increase the genetic risk to develop SCO.

Contribution of TEX15 genetic variants to the risk of developing severe non-obstructive oligozoospermia.

Background: Severe spermatogenic failure (SPGF) represents one of the most relevant causes of male infertility. This pathological condition can lead to extreme abnormalities in the seminal sperm count, such as severe oligozoospermia (SO) or non-obstructive azoospermia (NOA). Most cases of SPGF have an unknown aetiology, and it is known that this idiopathic form of male infertility represents a complex condition. In this study, we aimed to evaluate whether common genetic variation in TEX15, which encodes a key player in spermatogenesis, is involved in the susceptibility to idiopathic SPGF. Materials and Methods: We designed a genetic association study comprising a total of 727 SPGF cases (including 527 NOA and 200 SO) and 1,058 unaffected men from the Iberian Peninsula. Following a tagging strategy, three tag single-nucleotide polymorphisms (SNPs) of TEX15 (rs1362912, rs323342, and rs323346) were selected for genotyping using TaqMan probes. Case-control association tests were then performed by logistic regression models. In silico analyses were also carried out to shed light into the putative functional implications of the studied variants. Results: A significant increase in TEX15-rs1362912 minor allele frequency (MAF) was observed in the group of SO patients (MAF = 0.0842) compared to either the control cohort (MAF = 0.0468, OR = 1.90, p = 7.47E-03) or the NOA group (MAF = 0.0472, OR = 1.83, p = 1.23E-02). The genotype distribution of the SO population was also different from those of both control (p = 1.14E-02) and NOA groups (p = 4.33-02). The analysis of functional annotations of the human genome suggested that the effect of the SO-associated TEX15 variants is likely exerted by alteration of the binding affinity of crucial transcription factors for spermatogenesis. Conclusion: Our results suggest that common variation in TEX15 is involved in the genetic predisposition to SO, thus supporting the notion of idiopathic SPGF as a complex trait.

Effect and in silico characterization of genetic variants associated with severe spermatogenic disorders in a large Iberian cohort.

BACKGROUND: Severe spermatogenic failure (SpF) represents the most extreme manifestation of male infertility, as it decreases drastically the semen quality leading to either severe oligospermia (SO, <5 million spermatozoa/mL semen) or non-obstructive azoospermia (NOA, complete lack of spermatozoa in the ejaculate without obstructive causes). OBJECTIVES: The main objective of the present study is to analyze in the Iberian population the effect of 6 single-nucleotide polymorphisms (SNPs) previously associated with NOA in Han Chinese through genome-wide association studies (GWAS) and to establish their possible functional relevance in the development of specific SpF patterns. MATERIALS AND METHODS: We genotyped 674 Iberian infertile men (including 480 NOA and 194 SO patients) and 1058 matched unaffected controls for the GWAS-associated variants PRMT6-rs12097821, PEX10-rs2477686, CDC42BPA-rs3000811, IL17A-rs13206743, ABLIM1-rs7099208, and SOX5-rs10842262. Their association with SpF, SO, NOA, and different NOA phenotypes was evaluated by logistic regression models, and their functional relevance was defined by comprehensive interrogation of public resources. RESULTS: ABLIM1-rs7099208 was associated with SpF under both additive (OR = 0.86, p = 0.036) and dominant models (OR = 0.78, p = 0.026). The CDC42BPA-rs3000811 minor allele frequency was significantly increased in the subgroup of NOA patients showing maturation arrest (MA) of germ cells compared to the remaining NOA cases under the recessive model (OR = 4.45, p = 0.044). The PEX10-rs2477686 SNP was associated with a negative testicular sperm extraction (TESE) outcome under the additive model (OR = 1.32, p = 0.034). The analysis of functional annotations suggested that these variants affect the testis-specific expression of nearby genes and that lincRNA may play a role in SpF. CONCLUSIONS: Our data support the association of three previously reported NOA risk variants in Asians (ABLIM1-rs7099208, CDC42BPA-rs3000811, and PEX10-rs2477686) with different manifestations of SpF in Iberians of European descent, likely by influencing gene expression and lincRNA deregulation.

Intronic variation of the SOHLH2 gene confers risk to male reproductive impairment.

OBJECTIVE: To evaluate whether SOHLH2 intronic variation contributes to the genetic predisposition to male infertility traits, including severe oligospermia (SO) and different nonobstructive azoospermia (NOA) clinical phenotypes. DESIGN: Genetic association study. SETTING: Not applicable. PATIENT(S): Five hundred five cases (455 infertile patients diagnosed with NOA and 50 with SO) and 1,050 healthy controls from Spain and Portugal. INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): Genomic DNA extraction from peripheral blood mononuclear cells, genotyping of the SOHLH2 polymorphisms rs1328626 and rs6563386 using the TaqMan allelic discrimination technology, case-control association analyses using logistic regression models, and exploration of functional annotations in publicly available databases. RESULT(S): Evidence of association was observed for both rs6563386 with SO and rs1328626 with unsuccessful sperm retrieval after testicular sperm extraction (TESE-) in the context of NOA. A dominant effect of the minor alleles was suggested in both associations, either when the subset of patients with the manifestation were compared against the control group (rs6563386/SO: P=.021, odds ratio [OR] = 0.51; rs1328626/TESE-: P=.066, OR = 1.46) or against the group of patients without the manifestation (rs6563386/SO: P=.014, OR = 0.46; rs1328626/TESE-: P=.012, OR = 2.43). The haplotype tests suggested a combined effect of both polymorphisms. In silico analyses evidenced that this effect could be due to alteration of the isoform population. CONCLUSION(S): Our data suggest that intronic variation of SOHLH2 is associated with spermatogenic failure. The genetic effect is likely caused by different haplotypes of rs6563386 and rs1328626, which may predispose to SO or TESE- depending on the specific allelic combination.

New Opportunities for Endometrial Health by Modifying Uterine Microbial Composition: Present or Future?

Current knowledge suggests that the uterus harbours its own microbiota, where the microbes could influence the uterine functions in health and disease; however, the core uterine microbial composition and the host-microbial relationships remain to be fully elucidated. Different studies are indicating, based on next-generation sequencing techniques, that microbial dysbiosis could be associated with several gynaecological disorders, such as endometriosis, chronic endometritis, dysfunctional menstrual bleeding, endometrial cancer, and infertility. Treatments using antibiotics and probiotics and/or prebiotics for endometrial microbial dysbiosis are being applied. Nevertheless there is no unified protocol for assessing the endometrial dysbiosis and no optimal treatment protocol for the established dysbiosis. With this review we outline the microbes (mostly bacteria) identified in the endometrial microbiome studies, the current treatments offered for bacterial dysbiosis in the clinical setting, and the future possibilities such as pro- and prebiotics and microbial transplants for modifying uterine microbial composition.

Evaluation of Male Fertility-Associated Loci in a European Population of Patients with Severe Spermatogenic Impairment.

Infertility is a growing concern in developed societies. Two extreme phenotypes of male infertility are non-obstructive azoospermia (NOA) and severe oligospermia (SO), which are characterized by severe spermatogenic failure (SpF). We designed a genetic association study comprising 725 Iberian infertile men as a consequence of SpF and 1058 unaffected controls to evaluate whether five single-nucleotide polymorphisms (SNPs), previously associated with reduced fertility in Hutterites, are also involved in the genetic susceptibility to idiopathic SpF and specific clinical entities. A significant difference in the allele frequencies of USP8-rs7174015 was observed under the recessive model between the NOA group and both the control group (p = 0.0226, OR = 1.33) and the SO group (p = 0.0048, OR = 1.78). Other genetic associations for EPSTI1-rs12870438 and PSAT1-rs7867029 with SO and between TUSC1-rs10966811 and testicular sperm extraction (TESE) success in the context of NOA were observed. In silico analysis of functional annotations demonstrated cis-eQTL effects of such SNPs likely due to the modification of binding motif sites for relevant transcription factors of the spermatogenic process. The findings reported here shed light on the molecular mechanisms leading to severe phenotypes of idiopathic male infertility, and may help to better understand the contribution of the common genetic variation to the development of these conditions.

Application of a sperm survival test: Results from an external quality control programme.

OBJECTIVE: The study aim is to determine which type of material - pipette tips or culture medium - is more appropriate for use in a cytotoxicity external quality control programme (CT-EQC). STUDY DESIGN: The results of the participating laboratories in Spanish CT-EQC programme for human reproduction laboratories during the period 2013-2016 were analyzed. Per year, laboratories receiving three pipette tips and three aliquots of culture medium. All laboratories used the human sperm survival test to perform the bioassay. On average 48 laboratories took part in the programme each year. Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) and overall accuracy were calculated, with the corresponding 95% confidence intervals. RESULTS: Overall, for both products, sensitivity was higher than specificity, and NPV was higher than PPV. For laboratories participating for the first time in the CT-EQC, lower results were obtained in sensitivity and specificity in culture media than in pipette tips. However, in subsequent years, these differences disappeared. The PPV obtained for pipette tips was higher than that obtained for culture media (0.82 (0.77-0.87) vs 0.71 (0.66-0.76)). No relationship was recorded between the laboratories' accuracy in culture media and pipette tips (r = 0.026). CONCLUSIONS: From a logistical standpoint, pipette tips are more appropriate than culture medium for use in a CT-EQC programme.

Obstetric and neo-natal outcomes of ICSI cycles using pentoxifylline to identify viable spermatozoa in patients with immotile spermatozoa.

Pentoxifylline (PF) represents an effective tool in stimulating motility and identifying viable spermatozoa in intracytoplasmic sperm injection (ICSI) patients presenting exclusively with immotile spermatozoa. However, its use is not universally accepted for its possible detrimental effects on oocytes, embryos or newborns. To evaluate whether PF use may affect obstetrical/neo-natal outcomes, 102 patients achieving a clinical pregnancy after a PF-ICSI in four IVF units in Spain and Italy were followed up after delivery. Neo-natal malformations were classified according to the World Health Organization International Classification of Diseases (ICD-10, range Q00-Q99). Malformation rate was compared with data published by other groups regarding children conceived by conventional IVF or ICSI reporting a 5.3% and 4.4% frequency of ICD-10 codes, respectively. Of 134 clinical pregnancies, 122 babies (82 singletons and 40 twins) were registered. Among singletons, the rates of low birthweight (≤2500 g) and preterm birth (<37 weeks) were 6.1% and12%, respectively. Regarding malformation rate per live births, 4/122 (3.3%, 95% confidence interval: 0.9-8.2%) babies with ICD-10 malformations were recorded. This is the first report on neo-natal outcomes deriving from PF-ICSI. Although based on a limited cohort, results do not suggest an increase of adverse outcomes, including malformation rates, following this procedure.

Maximum number of children per sperm donor based on false paternity rate.

PURPOSE: The aim of this study is to estimate the weight of each relevant factor in such unions of inadvertent consanguinity and to determine a "reasonable" limit for the number of children per donor, matching the probability of inadvertent consanguinity arising from the use of sperm donor in assisted reproduction with that of such a union arising from false paternity. METHODS: In this study, we applied to Spanish data a mathematical model of consanguineous unions, taking into account the following factors: maximum number of live births/donor, fertility rate, average number of births per donor in a pregnancy, donor success rate, matings per phenotype, number of newborns/year, and number of donors needed in the population/year and births by false paternity. RESULTS: In Spain, the number of inadvertent unions between descendants of the same donor in Spain has been estimated at 0.4/year (one every two and a half years), although this frequency decreases as the reference population increases. On the other hand, the frequency of unions between family members due to false paternity has been estimated at 6.1/year. Thus, only 6% of such unions are due to the use of donor sperm. CONCLUSION: A total of 25 children per sperm donor are needed to align the probability of inadvertant consanguinity arising from the use of assisted reproduction with that due to false paternity. Therefore, we consider this number to be the maximum "reasonable" number of children born per donor in Spain.

Economic evaluation of elective single-embryo transfer with subsequent single frozen embryo transfer in an in vitro fertilization/intracytoplasmic sperm injection program.

OBJECTIVE: To analyze the cost-effectiveness of IVF-ICSI cycles with elective single-embryo transfer (eSET), plus elective single frozen embryo transfer (eSFET) if pregnancy is not achieved, compared with double-embryo transfer (DET). DESIGN: Cost-effectiveness analysis. SETTING: Public hospital. PATIENT(S): A population of 121 women (<38 years old), undergoing their first or second IVF cycles. INTERVENTION(S): We conducted a cost-effectiveness analysis using the results of a prospective clinical trial. The women in group 1 received eSET plus eSFET, and those in group 2 received DET. A probabilistic sensitivity analysis was performed. MAIN OUTCOME MEASURE(S): Live birth delivery rate. RESULT(S): The cumulative live birth delivery rate was 38.60% in the eSET+eSFET group versus 42.19% in the DET group. The mean costs per patient were €5,614.11 in the eSET+eSFET group and €5,562.29 in the DET group. These differences were not statistically significant. The rate of multiple gestation was significantly lower in the eSET group than in the DET group (0 vs. 25.9%). CONCLUSION(S): This study does not show that eSET is superior to DET in terms of effectiveness or of costs. The lack of superiority of the results for the eSET+eSFET and the DET groups corroborates that the choice of strategy to be adopted should be determined by the context of the health care system and the individual prognosis.

Sex prediction from the femur and hip bone using a sample of CT images from a Spanish population.

Sex estimation and the analysis of sexual dimorphism is an essential part of forensic and archaeological studies of skeletons. However, osteologists often have to rely on single measurements, such as femoral head diameters, to estimate sex, especially when skeletons are incomplete. We have obtained a sex-prediction model based on CT images by applying the logistic regression technique to the measurements obtained for the proximal femoral epiphyses and coxal. Nine variables for 114 Spaniards (58 females and 56 males) of known age and sex from a region close to Madrid have been studied. The prediction equation obtained using these nine variables correctly classifies 99.1 % of these individuals. Reducing the equation to the three most explanatory variables (VDH, HDH and MIB) resulted in the correct classification of 98.3 %. These findings suggest that this procedure is highly effective for sex prediction. However, a lack of expertise may produce biases in the measurements obtained from CT images. Moreover, these equations are only most effective for the population for which they were calculated as human growth and body size are sensitive to nutritional variations, environmental stress and the so-called secular trend.

Cumulative live birth rate after two single frozen embryo transfers (eSFET) versus a double frozen embryo transfer (DFET) with cleavage stage embryos: a retrospective cohort study.

PURPOSE: According to the latest ART report for Europe, about 13% of pregnancies after frozen embryo transfer are multiple. Our objective was to analyse the impact on the multiple pregnancy rate of two eSFET (elective single frozen embryo transfers) versus a DFET (double frozen embryo transfer) in women aged under 38 years, who had not achieved pregnancy in their fresh transfer and who had at least two vitrified embryos of A/B quality. METHODS: This study was conducted from January 2010 to June 2013 at a public hospital. The couples were divided into three groups. Group DFET: the first cryotransfer of two embryos (105 women); cSFET group: the only cryotransfer of a single vitrified embryo (60 women); eSFET group, individually vitrified embryos: 20 patients included in a clinical trial of single-embryo fresh and frozen transfer and 21 patients who chose to receive eSFET. RESULTS: The clinical pregnancy rate was 38.1% in the DET group and the cumulative clinical pregnancy rate was 43.3% in the eSFET group. There were no significant differences between the DFET and eSFET groups (30.0 vs 34.1%) in cumulative live birth delivery rate. The rate of multiple pregnancies varied significantly between the DFET and eSFET groups (32.5 vs 0%, p < 0.05). CONCLUSIONS: For good-prognosis women aged under 38 years, taking embryo quality as a criterion for inclusion, an eSFET policy can be applied, achieving acceptable cumulative clinical pregnancy and live birth rates and reducing multiple pregnancy rates.

Randomised clinical trial comparing elective single-embryo transfer followed by single-embryo cryotransfer versus double embryo transfer.

OBJECTIVE: To analyze the impact of the eSET followed by single-embryo cryotransfer versus double embryo transfer in older women (<38 years) without taking into account embryo quality. STUDY DESIGN: This is a prospective randomised clinical trial performed on 194 couples attempting a first IVF cycle in a Public Hospital in Spain. The women in Group 1 received eSET plus a single-embryo cryotransfer, and those in Group 2 received a double embryo transfer (DET). RESULTS: In the intention-to-treat analysis, the cumulative live birth delivery rate in the eSET group was similar to the results obtained for the DET group (45.2% vs. 41.8%; p = 0.60). The rate of multiple gestation was significantly lower in the eSET group than in the DET group (0% vs. 26.4%; p < 0.05). The findings obtained in the per-protocol analysis were similar to those obtained in the intention-to-treat analysis. The per-protocol analysis revealed no significant differences in the rate of implantation (29.8% in eSET vs. 29.7% in DET; p = 0.98), in cumulative pregnancy rates per transfer (49.1% in eSET vs. 46.9% in DET; p = 0.80) or in the cumulative live birth delivery rate (38.6% in eSET vs. 42.2% in DET; p = 0.69). In the cycles with eSET, there were no twin pregnancies (0% in eSET vs. 27.6 in DET; p < 0.05). CONCLUSIONS: For women aged under 38 years with good prognosis, without taking embryo quality as a criterion for inclusion, an eSET policy can be applied, achieving acceptable cumulative clinical pregnancy rates and birth rates.

Assisted reproductive technology and obstetric outcome in couples when the male partner has a chronic viral disease.

BACKGROUND: Assisted reproductive technology (ART) with washed semen can achieve pregnancy with minimal risk of horizontal and vertical transmission of chronic viral diseases (CVD) such as human immunodeficiency virus (HIV), hepati- tis C virus (HCV) and hepatitis B virus (HBV) among serodiscordant couples. How- ever, few studies have been made of the use made by these couples of ARTs or of the obstetric results achieved. MATERIALS AND METHODS: In this retrospective study, 93 men who were seropositive for HIV, HCV or HBV and who underwent assisted reproduction treatment at our centre (Hospital Universitario Virgen de las Nieves, Granada, Spain) were included. Washed semen was tested to detect viral particles. Non-infected women were tested before and after each treatment, as were the neonates at birth and after three months. RESULTS: A total of 62 sperm samples were washed, and none were positive for the detec- tion of viral molecules. Semen samples from 34 HBV positive males were not washed since the female partner had immunity to hepatitis B. In total, 38 clinical pregnancies were achieved (22% per cycle and 40.9% per couple) out of 173 cycles initiated, and 28 births were achieved (16.2% per cycle and 30.1% per couple), producing 34 live births. The rate of multiple pregnancies was 21.4%. Obstetric and neonatal results were similar in the groups of couples studied. At follow-up, no seroconversion was detected in the women or neonates. CONCLUSION: Sperm washing and intracytoplasmic sperm injection are shown to be a safe and effective option for reducing the risk of transmission or super infection in serodiscordant or concordant couples who wish to have a child. Pregnancies ob- tained by ART in couples when the male is CVD infected achieve good obstetric and neonatal results.

Reducing inter-observer variability in embryo evaluation by means of training courses.

PURPOSE: To study the utility of a training session offered to junior embryologists, comparing the results obtained with those reported by a group of senior embryologists. METHODS: The 62 junior embryologists participanting were asked to decide on the quality of the embryos and theg clinical decision to be taken. RESULTS: The junior embryologists' success rate following the training course was significantly higher than before for embryo classification (48.4% ± 20.4 vs. 59.7% ±16.7) (p < 0.05) and for clinical decision (54.7% ± 19.6 vs. 68.7% ± 17.6) (p < 0.005). Comparison of the degree of agreement between the categories assigned by the junior embryologists and those assigned by consensus among the group of senior embryologists revealed kappa values of k = 0.32 before the course and of k = 0.54 after it. The comparison between pre- and post-training junior and senior embryologists also reflected an improvement in the kappa index for clinical decision, from k = 0.54 to k = 0.68. CONCLUSIONS: Training courses are shown to be an effective tool for increasing the degree of agreement between junior and senior embryologists.

PGS-FISH in reproductive medicine and perspective directions for improvement: a systematic review.

INTRODUCTION: Embryo selection can be carried out via morphological criteria or by using genetic studies based on Preimplantation Genetic Screening. In the present study, we evaluate the clinical validity of Preimplantation Genetic Screening with fluorescence in situ hybridization (PGS-FISH) compared with morphological embryo criteria. MATERIAL AND METHODS: A systematic review was made of the bibliography, with the following goals: firstly, to determine the prevalence of embryo chromosome alteration in clinical situations in which the PGS-FISH technique has been used; secondly, to calculate the statistics of diagnostic efficiency (negative Likelihood Ratio), using 2 × 2 tables, derived from PGS-FISH. The results obtained were compared with those obtained from embryo morphology. We calculated the probability of transferring at least one chromosome-normal embryo when it was selected using either morphological criteria or PGS-FISH, and considered what diagnostic performance should be expected of an embryo selection test with respect to achieving greater clinical validity than that obtained from embryo morphology. RESULTS: After an embryo morphology selection that produced a negative result (normal morphology), the likelihood of embryo aneuploidies was found to range from a pre-test value of 65% (prevalence of embryo chromosome alteration registered in all the study groups) to a post-test value of 55% (Confidence interval: 50-61), while after PGS-FISH with a negative result (euploid), the post-test probability was 42% (Confidence interval: 35-49) (p < 0.05). The probability of transferring at least one euploid embryo was the same whether 3 embryos were selected according to morphological criteria or whether 2, selected by PGS-FISH, were transferred. Any embryo selection test, if it is to provide greater clinical validity than embryo morphology, must present a LR-value of 0.40 (Confidence interval: 0.32-0.51) in single embryo transfer, and 0.06 (CI: 0.05-0.07) in double embryo transfer. DISCUSSION: With currently available technology, and taking into account the number of embryos to be transferred, the clinical validity of PGS-FISH, although superior to that of morphological criteria, does not appear to be clinically relevant.

External quality control for embryology laboratories.

Participation in external quality control (EQC) programmes is recommended by various scientific societies. Results from an EQC programme for embryology laboratories are presented. This 5-year programme consisted of the annual delivery of (i) materials to test toxicity and (ii) a DVD/CD-ROM with images of zygotes and embryos on days 2 and 3, on the basis of which the participants were asked to judge the embryo quality and to take a clinical decision. A high degree of agreement was considered achieved when over 75% of the laboratories produced similar classifications. With respect to the materials analysed, the specificity was 68% and the sensitivity was 83%. Concerning embryo classification, the proportion of embryos on which a high degree of agreement was achieved increased during this period from 35% to 55%. No improvement was observed in the degree of agreement on the clinical decision to be taken. Day-3 embryos produced a higher degree of agreement (58%) than did day-2 embryos (32%) (P<0.05). Participation in EQC increased the degree of inter-laboratory agreement on embryo classification, but not the corresponding agreement on clinical decision taking. It is necessary to introduce measures aimed at standardizing decision taking procedures in embryology laboratories.