Factors associated with embryo mosaicism: a systematic review and meta-analysis

PURPOSE

Evaluate which factors are involved in the increased rate of mosaicism in embryos.

METHODS

A systematic review and meta-analysis was performed. After an exhaustive search of the literature, a total of seven papers were included in the analysis. In addition, data collected from IVF cycles performed in our fertility clinic were also analysed. Day of biopsy, embryo quality, maternal and paternal age and seminal quality were the chosen factors to be studied.

RESULTS

The results of the meta-analysis show that neither embryo quality nor seminal quality were related to mosaic embryo rate (OR: 1.09; 95% CI: 0.94-1.28 and OR: 1.10; 95% CI: 0.87-1.37, respectively). A positive association was observed for the variable "biopsy day" with embryos biopsied at day 6 or 7 having the highest rate of mosaicism (OR: 1.06; 95% CI: 1.01-1.11). In opposite to what happens with aneuploidy rate, which increases with maternal age, embryo mosaicism is higher in younger women (<34 years) rather than in older ones (≥34 years) (OR: 0.95; 95% CI: 0.92-0.98). However, for the "paternal age" factor, no association with mosaicism was found (OR: 1.04; 95% CI: 0.90-1.21).

CONCLUSIONS

With the present study, we can conclude that the factors related to the presence of mosaicism in embryos are the embryo biopsy day and maternal age. The rest of the studied factors showed no significant relationship with mosaicism. These results are of great importance as knowing the possible causes leading to mosaicism helps to improve the clinical results of reproductive treatments.

Identification of novel candidate genes associated with meiotic aneuploidy in human embryos by whole-exome sequencing

PURPOSE

To identify novel genetic variants responsible for meiotic embryonic aneuploidy.

METHODS

A prospective observational cohort study that included 29 couples who underwent trophectoderm biopsies from 127 embryos and performed whole-exome sequencing (WES) between November 2019 and March 2022. Patients were divided into two groups according to the expected embryo aneuploidy rate based on maternal age.

RESULTS

After variant filtering in the WES analysis of 58 patients/donors, five heterozygous variants were identified in female partners from the study group that had an impact on embryo aneuploidy. Additionally, a slowdown in embryo development and a decrease in the number of blastocysts available for biopsy were observed in the study group embryos.

CONCLUSION

This study has identified new candidate genes and variants not previously associated with meiotic embryo aneuploidy, but which are involved in important biological processes related to cell division and chromosome segregation. WES may be an efficient tool to identify patients with a higher-than-expected risk of embryo aneuploidy based on maternal age and allow for individualized genetic counselling prior to treatment.

IL-6/IL-10 and IL-1β/IL-4 ratios associated with poor ovarian response in women undergoing in-vitro fertilization

The aim of this work was to evaluate whether serum cytokines levels are associated with ovarian response in IVF. 149 patients were included in a retrospective study. Cytokines IL-2, IL-4, IL- 6, IL-8, IL-10, VEGF, IFNγ, TNFα, IL-1α, IL-1β, MCP-1 and EGF were measured by sandwich immunoassay previously to ovarian stimulation. Performing hierarchical cluster analysis, we observed that the antral follicle count, the total oocytes recovered and the MII recovered are grouped in the same cluster as the cytokines IL-2-4-6-10-1α-1β, IFNγ y TNFα. Then, we found that the ratio between IL and 6 and IL-10 was higher in low responder women (2.15 versus 1.55; p = 0.035). If we establish 0.9 as a cut-off for the IL-6/IL-10, we observed that above this value the risk of having a low response to ovarian stimulation was more than 3 times greater than below this value (22.9 % versus 6.0 %; p = 0.007). Also, the ratio IL-1β/IL-4 was higher in patients with normal or suboptimal response (0.62 versus 0.34; p = 0.034) and any patient with low response had a value greater than 0.7 (p = 0.003). As a conclusion, the IL-6/IL-10 and IL-1β/IL-4 ratios showed differences between normoresponder women and patients with low ovarian response.

Identification of new variants and candidate genes in women with familial premature ovarian insufficiency using whole-exome sequencing

PURPOSE

To identify candidate variants in genes possibly associated with premature ovarian insufficiency (POI).

METHODS

Fourteen women, from 7 families, affected by idiopathic POI were included. Additionally, 98 oocyte donors of the same ethnicity were enrolled as a control group. Whole-exome sequencing (WES) was performed in 14 women with POI to identify possibly pathogenic variants in genes potentially associated with the ovarian function. The candidate genes selected in POI patients were analysed within the exome results of oocyte donors.

RESULTS

After the variant filtering in the WES analysis of 7 POI families, 23 possibly damaging genetic variants were identified in 22 genes related to POI or linked to ovarian physiology. All variants were heterozygous and five of the seven families carried two or more variants in different genes. We have described genes that have never been associated to POI pathology; however, they are involved in important biological processes for ovarian function. In the 98 oocyte donors of the control group, we found no potentially pathogenic variants among the 22 candidate genes.

CONCLUSION

WES has previously shown as an efficient tool to identify causative genes for ovarian failure. Although some studies have focused on it, and many genes are identified, this study proposes new candidate genes and variants, having potentially moderate/strong functional effects, associated with POI, and argues for a polygenic etiology of POI in some cases.

O-025 Factors affecting biochemical pregnancy: Machine learning-assisted identification

Study question

What variables in a PGT-A cycle can influence biochemical pregnancy loss?

Summary answer

There are paternal, maternal, ovarian stimulation, endometrial and embryo biopsy factors that are associated with the rate of biochemical pregnancy after the euploid embryo transfer.

What is known already

Biochemical miscarriage is an early termination in the development of pregnancy. Embryonic chromosomal alterations have been proposed to cause biochemical pregnancy. However, even though euploid embryos are transferred in PGT-A cycles, biochemical pregnancy rates do not seem to be modified, so there must be other factors associated with this type of miscarriage.

The classical-statistical methods used to establish the factors related to biochemical miscarriage have produced contradictory results and there is no unanimity in the literature. As an alternative to traditional methods, different artificial intelligence algorithms are being used for the analysis of biological data.

Study design, size, duration

The study design is observational and retrospective. A total of 5892 embryos from 1919 PGT-A cycles were considered (January-2017 to October-2021). Only transferred embryos were included in the study (n = 1161). The trophoectoderm biopsies on D5, D6 or D7 blastocysts were analysed by NGS using the Illumina platform (VeriSeq Illumina®, San Diego, CA, USA). The biopsied embryos were vitrified and transferred in a subsequent cycle.

Participants/materials, setting, methods

Indications for PGT-A were advanced maternal age, altered karyotype or sperm FISH, history of chromosomal abnormalities in the offspring, repeated miscarriages and recurrent implantation failures.

Clinical outcomes were recorded in a database including additional potential factors (n = 48) associated with biochemical pregnancy and related to progenitors, embryos and their biopsy, ovarian stimulation and adjuvant treatments.

The association between the different variables and biochemical pregnancy was analysed using SPSS (v20.0) and R (v. 4.0.5) statistical software.

Main results and the role of chance

In order to determine which factors might increase biochemical pregnancy rates in euploid embryos, a multivariate analysis using logistic regression was initially performed. In the best predictive model (AUC=0.659) with a lower AIC (Akaike information criterion) value, only 3 factors showed a statistically significant association: uterine alterations (OR = 4.88, 95% CI [1.65-12.64]), day of embryo biopsy (OR = 2.19, 95% CI [1.46-3.31]) and mosaicism (number of altered chromosomes: OR = 1.59, 95% CI [1.10-2.22]) which significantly increased the risk of biochemical pregnancy.

To identify other variables that might modify biochemical pregnancy rates and could be missed by classic statistical methods, different types of machine learning algorithms were used: unsupervised model (cluster analysis) and supervised predictive models (support vector machines (AUC=0.845), k-nearest neighbors (AUC=0.858), random forest (AUC=0.853), neural networks multilayer (AUC=0.719) and gradient boosting (AUC=0.825).

The variables that had the greatest predictive power in the different machine learning algorithms were the variables associated with the embryo biopsy (day, number of laser pulses and biopsied cells), endometrial thickness and variables related to the male factor (sperm aneuploidy and DNA fragmentation). These algorithms apply different methodologies, but all agree on the fundamental role of these variables.

Limitations, reasons for caution

To confirm that the new identified variables are associated with biochemical pregnancy, it would be necessary to carry out prospective studies.

Wider implications of the findings

Biochemical pregnancy is the least studied clinical outcome in IVF. Knowledge of the variables that could affect biochemical pregnancy may be relevant as it may be a target for new therapies to reduce biochemical pregnancy rates and thus increase success rates.

Trial registration number

Not Applicable

P–605 Low serum progesterone on the day of frozen embryo transfer after artificial endometrial preparation: exploring the clinical impact of “rescue” strategies

Study question

Can we rescue treatments with low progesterone (PG) levels the day of frozen embryo transfer (FET) by adding subcutaneous progesterone?

Summary answer

After receiving additional supplementation with subcutaneous progesterone, women with low serum progesterone on cryotransfer day, have similar ongoing pregnancy rates as women with normal levels.

What is known already

Micronized vaginal progesterone fails to achieve optimal serum levels in up to 30% of patients receiving frozen embryos under artificial cycles (AC) despite the administration of 400 mg twice daily. Cancelling the thawing process and restarting a new treatment is a very disappointing option for patients and doctors. An alternative strategy is to administrate additional progesterone subcutaneously. The efficacy of the additional administration of subcutaneous progesterone as a “rescue” strategy in terms of clinical outcomes remains to be validated.

Study design, size, duration

We included 356 FET performed at Instituto Bernabeu between January 2019 - August 2020 in a retrospective case-control study. Groups were established according to PG levels on the day of the embryo transfer. The Control Group included: patients with optimal progesterone levels (≥8.8 ng ml); while the Rescue Group included those with suboptimal progesterone levels (&lt;8.8 ng ml).

Participants/materials, setting, methods

All patients performed frozen embryo transfer after artificial endometrial preparation. All embryo transfers were performed at blastocyst stage after 5 days of progesterone administration. Progesterone levels were assessed the day of the embryo transfer by an electrochemiluminescence immunoassay. Samples were obtained 2–5 hours after the last vaginal progesterone administration.

Primary outcome was Ongoing Pregnancy Rates (OPR). Secondary outcomes were pregnancy rates (PR), miscarriage rates (MR) and biochemical miscarriage (BM).

Main results and the role of chance

301 patients were included in the Control Group and 55 in the Rescue Group. No significant differences were found between both groups. OPR rate was 34.7% for patients in the control group versus 26.4% in the rescue group (p = 0.240)

PR was 52.5% for patients with optimal PG levels vs 54.5% when PG levels were below 8.8 ng/mL. Both BM and MR tend to be higher in women who had low serum PG: BM (21.4% vs 15.5%) and MR (28.6% vs 18.1%), without reaching significant statistical difference.

In addition, we analyzed data from a sub-group of patients who received extra subcutaneous progesterone (based on cliniciańs decision), despite having normal serum PG levels. No differences in clinical outcomes between these groups were observed either. OPR was 29%, vs 35.4% (p = 0.241), PR was 51.8% vs 53.7%; BM was 16.7% vs 16.3% and MR was 26.9% vs 17.1% between women who received an extra subcutaneous PG dose versus women who did not, respectively.

Weight and BMI distribution were homogeneous across groups. A discreet difference was observed in age distribution (control group mean age 41.6 years vs. 39.7 years in the rescue group).

Limitations, reasons for caution

The retrospective collection of data and a limited sample size constitutes the main limitations of the study. Significant statistical differences were not found between groups but still differences might be clinically relevant. Larger studies are needed to reach robust conclusions on the strategy.

Wider implications of the findings: In AC cycles, when supplemented with additional subcutaneous progesterone, women showing low serum progesterone on cryotransfer day may expect similar clinical outcomes as women with normal levels. Pending on confirmatory studies, this strategy could consider as an alternative to cycle cancellation.

Trial registration number

Not applicable

O-203 Application of machine learning to predict aneuploidy and mosaicism in embryos from in vitro fertilization (IVF) cycles

Study question

Is it possible to predict the likelihood of an IVF embryo being aneuploid and/or mosaic using a machine learning algorithm?

Summary answer

There are paternal, maternal, embryonic and IVF-cycle factors that are associated with embryonic chromosomal status that can be used as predictors in machine learning models.

What is known already

The factors associated with embryonic aneuploidy have been extensively studied. Mostly maternal age and to a lesser extent male factor and ovarian stimulation have been related to the occurrence of chromosomal alterations in the embryo.

On the other hand, the main factors that may increase the incidence of embryo mosaicism have not yet been established.

The models obtained using classical statistical methods to predict embryonic aneuploidy and mosaicism are not of high reliability. As an alternative to traditional methods, different machine and deep learning algorithms are being used to generate predictive models in different areas of medicine, including human reproduction.

Study design, size, duration

The study design is observational and retrospective. A total of 4654 embryos from 1558 PGT-A cycles were included (January-2017 to December-2020). The trophoectoderm biopsies on D5, D6 or D7 blastocysts were analysed by NGS. Embryos with ≤25% aneuploid cells were considered euploid, between 25-50% were classified as mosaic and aneuploid with &gt;50%.

The variables of the PGT-A were recorded in a database from which predictive models of embryonic aneuploidy and mosaicism were developed.

Participants/materials, setting, methods

The main indications for PGT-A were advanced maternal age, abnormal sperm FISH and recurrent miscarriage or implantation failure. Embryo analysis were performed using Veriseq-NGS (Illumina).

The software used to carry out all the analysis was R (RStudio). The library used to implement the different algorithms was caret. In the machine learning models, 22 predictor variables were introduced, which can be classified into 4 categories: maternal, paternal, embryonic and those specific to the IVF cycle.

Main results and the role of chance

The different couple, embryo and stimulation cycle variables were recorded in a database (22 predictor variables). Two different predictive models were performed, one for aneuploidy and the other for mosaicism. The predictor variable was of multi-class type since it included the segmental and whole chromosome alteration categories.

The dataframe were first preprocessed and the different classes to be predicted were balanced. A 80% of the data were used for training the model and 20% were reserved for further testing. The classification algorithms applied include multinomial regression, neural networks, support vector machines, neighborhood-based methods, classification trees, gradient boosting, ensemble methods, Bayesian and discriminant analysis-based methods. The algorithms were optimized by minimizing the Log_Loss that measures accuracy but penalizing misclassifications.

The best predictive models were achieved with the XG-Boost and random forest algorithms. The AUC of the predictive model

for aneuploidy was 80.8% (Log_Loss

1.028) and for mosaicism 84.1% (Log_Loss: 0.929). The best predictor variables of the models were maternal age, embryo quality, day of biopsy and whether or not the couple had a history of pregnancies with chromosomopathies. The male factor only played a relevant role in the mosaicism model but not in the aneuploidy model.

Limitations, reasons for caution

Although the predictive models obtained can be very useful to know the probabilities of achieving euploid embryos in an IVF cycle, increasing the sample size and including additional variables could improve the models and thus increase their predictive capacity.

Wider implications of the findings

Machine learning can be a very useful tool in reproductive medicine since it can allow the determination of factors associated with embryonic aneuploidies and mosaicism in order to establish a predictive model for both. To identify couples at risk of embryo aneuploidy/mosaicism could benefit them of the use of PGT-A.

Trial registration number

Not Applicable

P–546 Exome sequencing and preimplantation genetic testing for unexplained recurrent fetal malformations

Study question

Could patient suffering unexplained recurrent fetal malformations be benefit of PGT-M by exome sequencing mutations identification?

Summary answer

Patients suffering unexplained recurrent fetal malformations could be benefit of the use of exome sequencing in combination to PGT-M to have a healthy live birth.

What is known already

Fetal malformations account for approximately 3% of live births and causes include: chromosomal abnormalities, exposure to toxic substances or teratogens and infections. Recently, studies have shown that several monogenic diseases are linked to fetal abnormalities. However, because of the large number of potential genes, genetic testing is challenging. Exome sequencing is widely used to detect genetic mutations and has emerged as a useful tool for finding the genetic cause of fetal abnormalities. The aim of this study was to show how exome sequencing in patients suffering unexplained recurrent fetal malformations in combination to PGT-M could lead to successful healthy newborn.

Study design, size, duration

Case report of a non-consanguineous couple with unexplained, recurrent fetal malformations. Couple were recruited during clinical consultation for unexplained recurrent fetal malformations at a private reproductive medicine clinic. The couple had two malformed fetus with the same congenital abnormalities: hydrocephalus, cerebellar vermis agenesis, cerebellar hypoplasia and enlarged cisterna magna. Patients signed written informed consent regarding to exome testing. For fetal sample, informed consent was obtained from parents.

Participants/materials, setting, methods

Sample of the affected fetus were provided. Parental genomic DNA was extracted from peripheral blood. Exome sequencing was performed using TrusightOne (Illumina®). FASTAQ data were processed through BWA and GATK algorithm. VCF files were analysed using Variant Interpreter software. After genetic counselling, PGT-M was performed using linkage polymorphic markers analysis and mutation sequencing. Embryo biopsy was carried at blastocyst stage. Embryos were vitrified and one healthy embryo was thaw and transfer in a subsequent cycle.

Main results and the role of chance

An homozygous novel pathogenic mutation c.641 C&gt;T (p.Ala214Val) in FVLCR2 gene was found. The parents were heterozygous carriers revealing that the detected variant follow an autosomal recessive pattern. The FLVCR2 (14q24.3) gene encodes a transmembrane protein that belongs to the major facilitator superfamily of secondary carriers that transport small solutes in response to chemiosmosis ion gradients, such as calcium. Mutations in this gene are related to fetal central nervous system defects. This disorder is diagnosed prenatally and is lethal. PGT-M was recommended during genetic counselling. After control ovarian stimulation 14 oocytes were retrieved and finally 4 embryos were suitable for embryo biopsy at blastocyst stage. One embryo was diagnosed as healthy, two affected and one heterozygous carrier. The healthy embryo was thaw and transferred and a healthy male baby was born.

Limitations, reasons for caution

Exome sequencing has technical limitations: only covers mutations in coding regions and does not cover noncoding regions of the genome. It also cannot reliably detect copy-number variants at single gene level.

Wider implications of the findings: This study offers strong evidence of exome-sequencing as a new diagnostic strategy and powerful tool discovering the underlying etiology of recurrent fetal malformations and identifying new genes important for human development. Using this strategy in combination with PGT-M, clinicians can help couples with recurrent fetal malformations to have healthy newborns.

Trial registration number

Not applicable

P–541 Identification of novel variants and candidate genes in women with familial idiopathic premature ovarian failure using whole-exome sequencing

Study question

Is it possible to identify a genetic cause of familial premature ovarian failure (POF) with whole-exome sequencing (WES)?

Summary answer

Whole-exome sequencing is the most efficient strategy to identify probably pathogenic mutations in different genes in pathologies of polygenic etiology such as premature ovarian failure.

What is known already

Premature ovarian failure is the loss of ovarian function before the age of 40, and it is a common cause of infertility in women. This pathology has a heterogeneous etiology. Some chromosomal and genetic alterations have been described, and could explain approximately 20% of cases. However, in most patients the origin remains unknown. Recent studies with next-generation sequencing (NGS) have identified new variants in candidate genes related with premature ovarian insufficiency (POI) or premature ovarian failure (POF). These genes are not only involved in processes such as folliculogenesis, but also with DNA damage repair, homologous recombination, and meiosis.

Study design, size, duration

Fourteen women, from 7 families, affected by idiopathic POF were included in the study from October 2019 to September 2020. Seven POF patients were recruited when they came to our clinic to undergo assisted reproductive treatment. In the anamnesis, it was found that they had relatives with a diagnosis of POF, who were also recruited for the study. The inclusion criteria were amenorrhea before 38 years old and analytical and ultrasound signs of ovarian failure.

Participants/materials, setting, methods

WES was performed using TrusightOne (Illumina®). Sequenced data were aligned through BWA tool and GATK algorithm was used for SNVs/InDel identification. VCF files were annotated using Variant Interpreter software. Only the variants shared by each family were extracted for analysis and these criteria were followed: (1) Exonic/splicing variants in genes related with POF or involved in biological ovarian functions (2) Variants with minor allele frequency (MAF) ≤0.05 and (3) having potentially moderate/strong functional effects.

Main results and the role of chance

Seventy-nine variants possibly related with the POF phenotype were identified in the seven families. All these variants had a minor allele frequency (MAF) ≤0.05 in the gnomAD database and 1000 genomes project. Among these candidate variants, two were nonsense, six splice region, one frameshift, two inframe deletion and 68 missense. Thirty-two of the missense variants were predicted to have deleterious effects by minimum two of the four in silico algorithms used (SIFT, PolyPhen–2, MutationTaster and PROVEAN). All variants were heterozygous, and all the families carried three or more candidate variants. Altogether, 43 probably damaging genetic variants were identified in 39 genes expressed in the ovary and related with POF/POI or linked to ovarian physiology. We have described genes that have never been associated to POF pathology, however they may be involved in key biological processes for ovarian function. Moreover, some of these genes were found in two families, for example DDX11, VWF, PIWIL3 and HSD3B1. DDX11 may function at the interface of replication-coupled DNA repair and sister chromatid cohesion. VWF gene is suggested to be associated with follicular atresia in previous studies. PIWIL3 functions in development and maintenance of germline stem cells, and HSD3B1 is implicated in ovarian steroidogenesis.

Limitations, reasons for caution

Whole-exome sequencing has some limitations: does not cover noncoding regions of the genome, it also cannot detect large rearrangements, copy-number variants (large deletions/duplications), mosaic mutations, mutations in repetitive or high GC rich regions and mutations in genes with corresponding pseudogenes or other highly homologous sequences.

Wider implications of the findings: WES has previously shown to be an efficient tool to identify genes as cause of POF, and has demonstrated the polygenic etiology. Although some studies have focused on it, and many genes are identified, this study proposes new candidate genes and variants, having potentially moderate/strong functional effects, associated with POF.

Trial registration number

Not applicable

P–550 Clinical outcomes of mosaic embryos are similar between young and older women

Study question

Are there differences in the clinical outcomes of mosaic embryos depending on the female age?

Summary answer

Clinical outcomes of mosaic embryo transfers are similar regardless female age.

What is known already

Chromosomal abnormalities are common in embryos analyzed in preimplantation genetic testing for aneuploidy (PGT-A) cycles. Mosaicism (the presence of two or more chromosomally distinct cell lines) is a usual event in embryos derived from IVF cycles.

Several studies show that mosaic embryos have reduced potential to reach term, compared to euploid embryos. The factors affecting the implantation potential and development of mosaic embryos are controversial. Recently, Victor et al. (2019) argued that mosaic blastocysts generated at younger ages show better outcomes compared to older ages. The aim of this study was to test this hypothesis in our centre.

Study design, size, duration

A total of 136 mosaic embryos from patients undergoing PGT-A cycles from May 2014 to October 2020 were retrospectively analyzed in this study. The blastocyst trophoectoderm biopsies of day 5 and 6 were analysed by aCGH (n = 47, 30.1%) and NGS (n = 109, 69.9%). An embryo was considered mosaic when the percentage of aneuploid cells were 25–50% in aCGH and 20–50% in NGS. Only single embryo transfer cycles were included in the analysis.

Participants/materials, setting, methods

Embryo analysis were performed using Agilent SurePrint G3 8x60K CGH microarrays or Veriseq NGS (Illumina), with previous whole genome amplification. We evaluated if clinical results of mosaic embryos transfers in IVF cycles were correlated with female age. The main outcome measures were β-hCG, implantation rate and ongoing pregnancy rate. β-hCG was measured in blood 14 days after the embryo transfer and was considered positive when it was &gt;2 mUI/ml.The statistical analysis was performed with SPSSv20.0.

Main results and the role of chance

A total of 136 mosaic embryos were included in this study. Overall, we evaluated factors affecting embryo mosaicism implantation potential. Neither the percentage of mosaicism nor the segmental mosaicism were related to mosaic embryo implantation, pregnancy and ongoing pregnancy rates.

To evaluate the impact of female age in clinical outcomes, we established two different groups depending on whether mosaic blastocysts were generated from oocytes retrieved at young maternal ages (≤35 years; n = 62) or at older ages (&gt;35years; n = 74).

No differences were found between groups. Nonetheless, to reduce bias, embryo quality, percentage of mosaicism, segmental mosaicism and whether the transferred embryo was frozen or fresh were included as confounding factors.

The rate of positive β-hCG was similar between groups: 45.2% in ≤ 35y group vs 54.1% in &gt; 35y (p = 0.476). The implantation rate was also similar: 30.6% vs 39.2%% (p = 0.855), respectively. Furthermore, the ongoing pregnancy rate was higher in the &gt;35y group (35.1%), compared to the ≤35y group (19.4%) without reaching statistically significant differences (p = 0.245).

Limitations, reasons for caution

The sample size is a limitation. aCGH test and a different definition for mosaic embryo in terms of percentage of abnormal cells was employed in this study compared to Victor et. al. (2019) study. Larger prospective studies should evaluate the impact of maternal age in the outcome of mosaic embryos.

Wider implications of the findings: Our results challenge that female age is associated with clinical outcomes after the transfer of mosaic embryos. Comparable results were obtained in young and older women. Therefore, in the absence of euploid embryos, mosaic embryos might be considered for transfer and similar outcomes are expected regardless of the maternal age.

Trial registration number

Not applicable

P–630 Progesterone levels using pessaries of 400 mg of vaginal progesterone (Cyclogest®) in artificial cycles for frozen embryo transfer

Study question

Does the use of pessaries of 400 mg of micronized progesterone provide comparable results as pessaries of 200 mg x2, in terms of progesterone levels?

Summary answer

The administration of pessaries of Cyclogest® 400 mg reduces the probability of presenting suboptimal level of progesterone on the day of the embryo transfer.

What is known already

The endometrial preparation for frozen embryo transfer (FET) in Artificial Cycle (AC) with vaginally-administered progesterone, is one of the most common IVF procedures nowadays. Now, it has been shown that suboptimal progesterone levels on the day of the embryo transfer compromise the results of FET treatments. Recently, a new preparation of 400 mg vaginal pessaries has been introduced in the market of European countries. Efficacy of this new preparation has been studied in “fresh” IVF cycles but we lack the comparative studies in AC making it necessary to further investigate this area.

Study design, size, duration

Non-inferiority retrospective case-control trial based on 347 embryo transfer treatments with endometrial preparation in AC carried out at Instituto Bernabeu between January 2019 and July 2020. 153 patients received 1 pessary of 400 mg every 12 hours (group A) and 194 received 2 pessaries of 200 mg every 12 hours (group B). Sampled size calculation resulted in 182 patients required to detect a minimum difference of 2 ng/ml so sample was powered for the purpose.

Participants/materials, setting, methods

Patients receiving embryos in AC preparation were included. All embryo transfers were performed at blastocyst stage after 5 days of progesterone administration. Progesterone levels were assessed the day of the embryo transfer by an electrochemiluminescence immunoassay.Primary outcome was the incidence of suboptimal progesterone levels according with the cutoff value stablished in the literature at 8.8 ng/mL. Secondary outcomes were pregnancy rates (PR), clinical pregnancy rates (CPR), ongoing pregnancy rates (OPR) and miscarriage rates (MR).

Main results and the role of chance

Incidence of suboptimal levels of progesterone was significantly lower in the group of 400 mg (9,8% in Group A vs 19,7% in the Group B, p = 0.011). Given that there was an imbalance between groups in the body weight (66.9 +/- 14 vs. 61.9 +/- 13.165 kg, p &lt; 0.001) and BMI (24.63 +/- 4.861 vs. 22.54 +/- 3.092, p &lt; 0.001), we decided to perform a binary logistic regression setting patient’s weight and BMI as confounding variables. The result confirms a higher risk of suboptimal progesterone levels (&lt;8.8) with the 2x200 mg regimen (OR: 2.52 95%CI: 1.28–4.96; p = 0.007). Mean progesterone levels were similar in both groups (13,8035 ng/mL +/- 4.62159 vs. 13.9799 ng/mL +/- 7.73243 respectively, p = 0.146). No differences were observed in clinical outcomes: PR (52.3% vs. 53.1%, p = 0.881), BM (14.7% vs. 17.6%, p = 0.597), CM (20% vs. 18.6%, p = 0.819) and OPR (33.1% vs. 33.7%, p = 0.912). The subjective medical decision to administer additional progesterone from the day of the embryo transfer onwards (taking values other than 8.8 ng / mL as a reference), was significantly lower in the group of 400 mg (24,3% vs 37,3%, p = 0.009 ).

Limitations, reasons for caution

The inherent limitations of a retrospective analysis. The study was not powered to detect differences in clinical outcomes. Therefore, results other than progesterone levels should be interpreted with caution.

Wider implications of the findings: A single pessary of 400 mg minimizes the necessity of additional medication (usually subcutaneous progesterone). Presentation of 400 mg is superior to 2x200 providing adequate progesterone levels and patient comfort. Dose finding and pharmacokinetics studies of the vaginal administration will be necessary for the future to optimize FET under AC.

Trial registration number

NCT04722471

P–588 Follicle-stimulating hormone receptor genotype and its influence on the results of double ovarian stimulation in IVF cycles

Study question

Does the follicle-stimulating hormone receptor (FSHR) genotype influence the results of the ovarian stimulation treatment in the luteal phase?

Summary answer

All patients undergoing in-vitro fertilization benefit from luteal phase ovarian stimulation, regardless of their follicle-stimulating hormone receptor genotype.

What is known already

Previous studies suggest that FSH receptor polymorphism in position 680 influences the response to ovarian stimulation in the luteal phase. It was observed that patients with SS genotype seems to require a higher dose to obtain an optimal ovarian response. Later, it was reported that, in patients with SS genotype, a better performance seems to be obtained by administering highly purified urinary FSH while, in SN patients, better results were obtained with recombinant FSH. In patients with NN genotype, no differences were found. Our aim was to test whether this concept is applicable to ovarian stimulation in the luteal phase.

Study design, size, duration

One hundred and thirty-four patients were included in a retrospective study between July 2017 and September 2020. In these patients, a double stimulation protocol was carried out and the FSH receptor was genotyped either as part of the pre-treatment fertility tests or for the current study. Patients with a double stimulation treatment who could not be genotyped were excluded from the analysis.

Participants/materials, setting, methods

To genotype the 680 position of the FSH receptor, a real-time PCR for allelic discrimination was carried out using StepOnePlus™ Real-Time PCR System (Applied Biosystems™. Ref: 4376600). Non-parametic tests were used to study the differences between the groups. They were performed with the software R Statistical Software, version 4.0.3.

Main results and the role of chance

The results of ovarian stimulation in the luteal phase were better compared to the conventional follicular phase. Statistically significant differences (p &lt; 0.001) were found in the number of retrieved oocytes (5.06 versus 3.51), retrieved MII (4.13 versus 2.91), fertilized oocytes (3.22 versus 1.81) and blastocysts formed (1.79 versus 0.62). Furthermore, these differences remained regardless of the genotype for the 680 position of the FSH receptor in all groups (p &lt; 0.05).

In addition, better results were obtained in the luteal phase in patients who have been stimulated with the type of gonadotropin that already had better performance in the follicular phase for its genotype, that is, highly purified urinary FSH in SS patients and recombinant FSH in SN patients, compared to other types of gonadotropin (p &lt; 0.05).

We also observed that stimulation in the luteal phase lasts longer and consume more gonadotropins than in the follicular phase. This is especially notable in the case of patients with SS genotype, who required slightly higher consumption of gonadotropins compared to the other genotypes in the luteal phase, as had previously been observed in the follicular phase for this genotype.

Limitations, reasons for caution

The retrospective study design and the sample size could be a limitation. Furthermore, we cannot determine whether the improvement in luteal phase performance is related to differences in the physiological environment between phases of the cycle or is caused by a possible activation of the ovary from the previous stimulation.

Wider implications of the findings: All patients undergoing in-vitro fertilization seems to benefit from luteal phase ovarian stimulation, regardless of their genotype for FSHR. In addition, the pharmacogenetic recommendation when choosing the type of FSH for ovarian stimulation should be the same both in the follicular phase and in the luteal phase.

Trial registration number

Not applicable

P–540 A feasible diagnostic approach for the cryptic subtelomeric traslocations in early recurrent miscarriage patients by preimplantation genetic testing (PGT)

Study question

Could cryptic subtelomeric traslocations in early recurrent miscarriage patients be diagnosed by preimplantation genetic testing?

Summary answer

PGT is a powerful tool to detect subtelomeric cryptic traslocations identifying the cause of early recurrent miscarriage and allowing subsequent genetic counselling. What is known already: Chromosome translocations are frequently associated with birth defects, spontaneous early pregnancy losses and infertility. However, submicroscopic traslocations (so-called cryptic traslocations) are too small to be detected by conventional karyotyping.. Due to balanced status, high resolution molecular techniques as arrayCGH are not able to detect it. Thus, cryptic traslocations detection is challenging. PGT is able to detect CNVs at higher resolution than routine karyotyping. Therefore, the recurrent diagnosis of CNV at embryo level could suggest a subchromosomal parental traslocation. The aim of this study is to investigate the feasibility of using PGT as an indicator of parental balanced cryptic traslocations.

Study design, size, duration

We included three couples who underwent PGT for unexplained repeated pregnancy loss (RPL) in our clinic from February 2020 to November 2020. Common established causes of RPL (uterine anomalies, antiphospholipid syndrome, immunological, hormonal and metabolic disorders) were previously rouled-out. Even couple karyotypes were normal. Twenty-three embryos from those couples were biopsied at blastocyst and analysed for CNVs detection using low coverage whole genome NGS.

Participants/materials, setting, methods

PGT by NGS was performed by Veriseq-NGS (Illumina), with previous whole genome amplification. Fluorescence in situ hybridization (FISH) using parental blood samples were performed to validate the origin of subchromosomal number variation. Commercially available subtelomeric specific probes were selected according to the CNV identified and the procedures were performed according to the manufacturer’s protocols.

Main results and the role of chance

Overall, CNVs of terminal duplication and deletion that imply unbalanced traslocation derivatives were detected in the 43.5% of biopsied embryos. For couple 1, 4 out of 5 embryos (80%) carried deletion of telomeric region on chromosomes 5 and 21. Three out of 6 biopsed embyos (50%) were diagnosed with subchromosomal copy variants at telomeric region on chromosomes 6 and 16 for couple 2. In the case of couple 3, three out of 12 embryos (25%) were carriers of CNV at subtelomeric region on chromosomes 2 and 6. The size of CNVs detected ranges from 8Mb to 20Mb. Accurate diagnosis with the parental study was made by FISH. The combination of probes to detect the structural chromosome alteration were: Tel5qter-LSI21q, Tel6pter-CEP16 and Tel6pter-CEP6 for each couple respectively. The FISH studies reveal that CNVs were inherited from one parent carrying the balanced cryptic traslocation. Ultimately, the abnormal karyotype from the carrier parent were 46,XY,t(5;21)(q33.2;q21.2) for couple 1, 46,XY,t(6;16)(p22.3;q22.1) for couple 2 and 46,XY,t(2;6)(p25.1;p24.2) for couple 3. Finally, each couple performed a cryotransfer of a single normal balanced embryo. Two pregnancies are ongoing.

Limitations, reasons for caution

The main limitation of this approach is the NGS- PGT resolution. CNVs smaller than 5Mb could not be detected.

Wider implications of the findings: This study shows the value of PGT for unexplained RPL, followed by parental FISH to better characterize CNVs and identify couples in whom one partner carries a cryptic translocation. Accurate diagnosis of parental chromosome translocation can achieve with FISH only, but FISH would not be performed unless PGT showed CNVs.

Trial registration number

Not applicable

Comprehensive mitochondrial DNA analysis and IVF outcome

STUDY QUESTION

Do mitochondrial DNA (mtDNA) copy number and heteroplasmy in human embryos affect the ongoing pregnancy rate?

SUMMARY ANSWER

Our study suggests that mtDNA copy number above a specific threshold is associated with the ongoing pregnancy rate.

WHAT IS KNOWN ALREADY

Mitochondria play a vital role in cell function. Recently, there has been increasing research on mtDNA as a biomarker of embryo implantation. Although reports showed that high levels of mtDNA in the blastocyst are associated with low implantation potential, other publications were unable to confirm this. Confounding factors may influence the mtDNA copy number in euploid embryos. On the other hand it has been speculated that both mtDNA heteroplasmy and copy number contribute to mitochondrial function. Next generation sequencing (NGS) allows us to study in depth mtDNA heteroplasmy and copy number simultaneously.

STUDY DESIGN, SIZE, DURATION

A prospective non-selection study was performed. We included 159 blastocyst biopsies from 142 couples who attended our clinic for preimplantation genetic testing for aneuploidies (PGT-A), from January 2017 to December 2017. All embryos were biopsied on Day 5 or Day 6. The aneuploid testing was performed by NGS. All blastocysts were diagnosed as euploid non-mosaic and were transferred. The mtDNA analysis was performed once the embryo diagnosis was known.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Sequencing reads mapping to the mtDNA genome were extracted from indexed bam files to identify copy number and heteroplasmy. The relative measure of mtDNA copy number was calculated by dividing the mtDNA reads by the nuclear DNA value to normalize for technical variants and the number of cells collected at the biopsy. All the results were subjected to a mathematical correction factor according to the embryo genome. Heteroplasmy was assigned by MitoSeek.

MAIN RESULTS AND THE ROLE OF CHANCE

The mean average copy number and SD of mtDNA per genome was 0.0016 ± 0.0012. Regarding heteroplasmy, 40 embryos were heteroplasmy carriers (26.32%). MtDNA variants were detected in coding and non-coding regions and the highest number of variants in an embryo was eight. With respect to IVF outcome for mtDNA copy number analysis, we set a threshold of 0.003 for the following analysis. The vast majority of the embryos were below the threshold (142/159, 89.31%) and 17 embryos were classified as having higher mtDNA levels. We showed a reduction in ongoing pregnancy rate associated with elevated mtDNA copy number (42.96% versus 17.65%, P < 0.05). This result was independent of maternal age and day of the biopsy: these factors were included as confounding factors because mtDNA copy number was negatively correlated with female age (25 –30 y: 0.0017 ± 0.0011, 30 –35 y: 0.0012 ± 0.0007, 35 –40 y: 0.0016 ± 0.0009, over 40 y: 0.0024 + 0.0017, P < 0.05). Embryos biopsied on Day 5 were more likely to have higher quantities of mtDNA compared with those biopsied on Day 6 (0.0017 versus 0.0009, P < 0.001). According to IVF outcome and heteroplasmy, a lower ongoing pregnancy rate was reported for embryos that carried more than two variants. However, this did not reach statistical significance when we compared embryos with a number of variants lower or higher than two (39.15 versus 20.0, P = 0.188). Finally, a clear positive association between the mtDNA variants and copy number was reported when we compare embryos with or without heteroplasmy (0.0013 ± 0.0009 versus 0.0025 ± 0.0014, P < 0.001) and among different numbers of variants (0:0.0013 ± 0.0009, 1–2:0.0023 ± 0.0012, >2:0.0043 ± 0.0014, P < 0.05).

LIMITATIONS, REASONS FOR CAUTION

A limitation may be the size of the sample and the high-throughput sequencing technology that might not have detected heteroplasmy levels below 2% which requires high sequence depth A clinical randomized trial comparing the clinical outcome after the transfer of embryos selected according to mtDNA levels or only by morphological evaluation will be necessary. More research into the impact of mtDNA heteroplasmy and copy number on IVF outcome is needed.

WIDER IMPLICATIONS OF THE FINDINGS

Our results demonstrate that embryos with elevated mtDNA copy number have a lower chance of producing an ongoing pregnancy. MtDNA copy number is higher in older women and is dependent upon the number of cell divisions that preceded biopsy. Moreover, our data suggest that mitochondrial activity could be a balance between functional capacity and relative mtDNA copy number.

STUDY FUNDING/COMPETING INTEREST(S)

There are no conflicts of interest or sources of funding to declare.

Trial registration number

Not applicable.

Effect of sex-sorting and cryopreservation on the post-thaw sperm quality of Iberian red deer spermatozoa

This study investigated the effect of sex-sorting and cryopreservation on post-thaw characteristics and fertility of red deer (Cervus elaphus) sperm for the first time. Semen was collected by electroejaculation from 10 mature stags during the breeding season, and each ejaculate split into four experimental groups: Bulk sorted spermatozoa, sorted but not sexed (BSS); sorted high purity X-spermatozoa (XSS); sorted high purity Y-spermatozoa (YSS); and, control non-sorted spermatozoa (NS). Following, all samples were frozen over liquid nitrogen. Two straws per stag and sample type were analyzed immediately post-thaw and following a 2-h incubation period at 37 °C. Post-thaw total motility (TM) as assessed by CASA was not different (P < 0.05) among NS, BSS and YSS sperm. For XSS, post-thaw TM was lower (39%, P < 0.05) than that for NS (54%) or BSS (50%), but similar (P > 0.05) to that of YSS (47%) sperm. The percentage of apoptotic spermatozoa as assessed by PI/YO-PRO-1 and flow cytometry analysis, was higher (17%, P ≤ 0.05) for XSS sperm than NS (12%), BSS (13%) and YSS (14%) sperm. Following incubation there were no differences (P > 0.05) in TM or percent apoptosis among treatments. Post-thaw chromatin stability calculated as the DNA fragmentation index (%DFI) was similar among treatments; following incubation %DFI increased in all except YSS, which displayed the lowest value (P < 0.05). Artificial insemination of synchronized hinds yielded 44, 52 and 62% delivery rates for YSS, NS and standard frozen-thawed sperm, respectively (P < 0.05). Notably, 93 and 55% of fawns born were males for the YSS and NS spermatozoa, respectively (P < 0.05). In summary, Y-sorted sperm displayed acceptable post-thaw sperm evaluation parameters and the expected offspring sex ratio. More studies are needed to understand the source of sperm damage that may compromise the fertility of Y-sorted red deer sperm.

Is targeted removal a suitable means for tuberculosis control in wild boar?

We assessed the suitability of targeted removal as a means for tuberculosis (TB) control on an intensely managed Eurasian wild boar (Sus scrofa) hunting estate. The 60km² large study area included one capture (treatment) site, one control site, and one release site. Each site was fenced. In the summers of 2012, 2013 and 2014, 929 wild boar were live-captured on the treatment site. All wild boar were micro-chipped and tested using an animal side lateral flow test immediately after capture in order to detect antibodies to the Mycobacterium tuberculosis complex (MTC). The wild boar were released according to their TB status: Seropositive individuals onto the release site (hunted after summer), and seronegative individuals back onto the treatment site. The annual summer seroprevalence of antibodies to the MTC declined significantly in live-captured wild boar piglets from the treatment site, from 44% in 2012 to 27% in 2013 (a reduction of 39%). However, no significant further reduction was recorded in 2014, during the third capture season. Fall-winter MTC infection prevalence was calculated on the basis of the culture results obtained for hunter-harvested wild boar. No significant changes between hunting seasons were recorded on either the treatment site or the control site, and prevalence trends over time were similar on both sites. The fall-winter MTC infection prevalence on the release site increased significantly from 40% in 2011-2012 to 64% in 2012-2013 and 2013-2014 (60% increase). Recaptures indicated a persistently high infection pressure. This experiment, the first attempt to control TB in wild boar through targeted removal, failed to reduce TB prevalence when compared to the control site. However, it generated valuable knowledge on infection pressure and on the consequences of translocating TB-infected wild boar.

Is the ideal mother a sensitive mother? Beliefs about early childhood parenting in mothers across the globe

In this article, we test the hypothesis that beliefs about the ideal mother are convergent across cultures and that these beliefs overlap considerably with attachment theory’s notion of the sensitive mother. In a sample including 26 cultural groups from 15 countries around the globe, 751 mothers sorted the Maternal Behavior Q-Set to reflect their ideas about the ideal mother. The results show strong convergence between maternal beliefs about the ideal mother and attachment theory’s description of the sensitive mother across groups. Cultural group membership significantly predicted variations in maternal sensitivity belief scores, but this effect was substantially accounted for by group variations in socio-demographic factors. Mothers living in rural versus urban areas, with a low family income, and with more children, were less likely to describe the ideal mother as highly sensitive. Cultural group membership did remain a significant predictor of variations in maternal sensitivity belief scores above and beyond socio-demographic predictors. The findings are discussed in terms of the universal and culture-specific aspects of the sensitivity construct.

The Effect of Oxidative Stress on Thawed Bulk-Sorted Red Deer Sperm

The aims of this study were to assess the effects of the sex-sorting process on post-thaw sperm quality as well as on induced oxidative stress damage (H2 O2 0 mm = H000; H2 O2 50 mm = H050; H2 O2 100 mm = H100) and the protective action of reduced glutathione (GSH) and Trolox, when comparing sorted (BSS) and non-sorted (NS) red deer spermatozoa incubated at 37°C. Sperm samples from three stags were collected by electroejaculation and frozen. Immediately after thawing, sperm motility was higher (p < 0.05) for NS (59% ± 3.3) than BSS (36.9% ± 5.8) sperm. Furthermore, the percentage of apoptotic sperm was higher (p < 0.05) for BSS (21.6% ± 5.0) than NS sperm (14.6% ± 1.2). The presence of H2 O2 increased DNA damage in NS (H000 = 4.1% ± 0.9; H050 = 9.3% ± 0.7; and H100 = 10.9% ± 2.3), but not in BSS sperm. However, in the presence of oxidant, GSH addition improved (p < 0.05) sperm motility in both groups of sperm samples as compared to their controls (NS: 44.5 ± 4.8 vs 21.1 ± 3.9 and BSS: 33.3 ± 8.1 vs 8.9 ± 1.8). These results demonstrate that the sperm-sorting process induces sublethal effects, albeit selecting a sperm population with a chromatin more resistant to oxidative stress than that in non-sorted sperm. Moreover, addition of GSH at 1 mm may be a good choice for maintaining the quality of stressed sperm samples, unlike Trolox, which inhibited sperm motility.

Operative start times and complications after liver transplantation

The recent national focus on patient safety has led to a re-examination of the risks and benefits of nighttime surgery. In liver transplantation, the hypothetical risks of nighttime operation must be weighed against either the well-established risks of prolonging cold ischemia or the potential risks of strategies to manipulate operative start times. A retrospective review was conducted of 578 liver transplants performed at a single institution between 1995 and 2008 to determine whether the incidence of postoperative complications correlated with operative start times. We hypothesized that no correlation would be observed between complication rates and operative start times. No consistent trends in relative risk of postoperative wound, vascular, biliary, or other complications were observed when eight 3-h time strata were compared. When two 12-h time strata (night, 3 p.m.-3 a.m., and day, 3 a.m.-3 p.m.) were compared, complications were not significantly different, but nighttime operations were longer in duration, and were associated a twofold greater risk of early death compared to daytime operations (adjusted OR 2.9, 95% CI 1.16-7.00, p = 0.023), though long-term survival did not differ significantly between the subgroups. This observation warrants further evaluation and underscores the need to explore and identify institution-specific practices that ensure safe operations regardless of time of day.

Prognostic value of the ankle-brachial index in elderly patients with a stable chronic cardiovascular event

BACKGROUND AND OBJECTIVES

Patients with polyvascular arterial disease have a greater risk of suffering a new atherothrombotic episode than those with involvement of only one vascular territory. We have studied the predictive prognostic value of the detection of non-diagnosed peripheral arterial disease, determined by measuring the ankle-brachial index in a population of elderly patients with stable chronic cardiac or cerebrovascular disease.

METHODS

This was a multicenter, prospective cohort study with consecutive inclusion of patients between 65 and 85 years of age with a previous atherothrombotic event, but without previously established peripheral arterial disease.

RESULTS

A total of 1096 patients were evaluated during 11.7 (+ or - 2.2) months of follow-up. An ankle-brachial index of < 0.9 was observed in 29.9% and > 1.4 in 6.9%. The detection of an ankle-brachial index < 0.9 was clearly associated with the presence of a combined primary event of cardiovascular death and non-fatal cardiovascular event [HR 1.99 (95% CI, 1.49-2.66; P < 0.001)]. There was also a significant relationship between ankle-brachial index > 1.4 and total (P = 0.001) or cardiovascular (P = 0.020) deaths. The predictive value of both ranges of the ankle-brachial index was maintained after adjusting for age, sex, diabetes mellitus, vascular territory, macroalbuminuria or glomerular filtration rate.

CONCLUSIONS

The detection of non-diagnosed peripheral arterial disease in patients with stable coronary or cerebrovascular events identifies a very high risk population that might benefit from more intensive treatment.

Learning two things at once: differential constraints on the acquisition and consolidation of perceptual learning

Learning is often prevented by events that occur after training, an outcome that is usually attributed to the disruption of consolidation-the transfer of learning to long-term memory. Here, we provide evidence from perceptual learning that improvements in performance can also be blocked by intervening events that occur during the acquisition phase of learning-the period of active practice. Listeners improved on each of two conditions of auditory temporal-interval discrimination (100 and 350 ms) when the two were practiced consecutively, even though that is a classic disruption-of-consolidation regimen. However, when practice on these two conditions was interleaved, there was no learning on either condition. The failure to improve in the interleaved case indicates that, at least in some circumstances, learning can be prevented during acquisition by events that do not disrupt consolidation itself. These results thus suggest that acquisition and consolidation are distinct phases in human learning.

Mesh plug and ureteral necrosis after kidney transplantation

CASE REPORT

We present a 59-year-old male who underwent living related kidney transplantation. During the procedure a previously placed mesh plug was found to be adherent to structures in the vicinity of the area of implantation. After revascularization, neocystouretostomy was performed with the ureter over the spermatic cord in order to avoid excessive dissection through this adherent mass. Shortly thereafter the patient was diagnosed with a ureteral leak and returned to the operating room. The intraoperative findings included adhesion of the ureter to the mesh plug with necrosis of its distal portion. A redo neocystouretostomy was performed. The patient recovered uneventfully.

CONCLUSION

This case report illustrates a unique cause of a urinary fistula related to mesh plug open inguinal hernia repair and demonstrates the importance of ensuring a safe distance between vital structures and any prosthetic device.

Body condition and protein supplementation positively affect periovulatory ovarian activity by non LH-mediated pathways in goats

Effects of rumen undegradable intake protein (UIP) supplementation on ovarian activity and serum insulin, GH, and LH were evaluated in goats having low or high body condition (BC). Goats with either low BC (n=16, 28.7+/-0.8 kg BW, BC=2.1+/-0.3) or high BC (n=16, 38.4+/-0.8 kg, BC=3.2+/-0.3) received, during 40-days, one of the two protein supplementation levels: without UIP or with UIP (120 g goat(-1)d(-1)). Oestrus was synchronized with two i.m. doses of PGF(2alpha), and jugular blood samples were collected from 36 to 42 h after the second prostaglandin injection at 15 min intervals. Serum concentrations of insulin, LH, and GH were measured The number of preovulatory follicles and the number of corpora lutea (CL) were evaluated by transrectal ultrasonography at 1 and 4 days after the second prostaglandin dose, respectively. Does with higher BC had more CL than those in the lower condition group (2.8+/-0.2 versus 1.8+/-0.2, P<0.05). Similarly, goats receiving UIP supplementation had more follicles (2.6+/-0.2 versus 1.9+/-0.2, P<0.05) and tended to have more CL (2.6+/-0.2 versus 2.0+/-0.2, P=0.05) than does not receiving UIP. Neither BCS nor UIP supplementation affected serum GH or LH concentrations, pulsatility, or area under the curve. High BC does produced more insulin (1.92+/-0.17 versus 0.81+/-0.17 ng/mL, P<0.01 ng/mL) than lower BC goats; the same for UIP-supplemented (1.69+/-0.18 versus 1.04+/-0.18, P<0.05). Results suggest that the increased ovarian activity observed in both UIP-supplemented and higher BC goats was not the result of changes in LH or GH, suggesting effects at a local level, through changes in insulin in a non-GnRH-gonadotrophin dependent manner.