MicroRNAs, secreted by the embryo in blastocoel fluid (BF) and embryo spent culture medium (SCM), regulate important cellular pathways controlling the stemness of inner cell mass, trophectoderm differentiation, and the dialogue between blastocyst and maternal tissues. In recent years, their role as non-invasive biomarkers of embryo quality has been deeply investigated. We compared the expression profiles of 96 microRNAs between BF and SCM from the same embryos, highlighting the differences between these two compartments. We found 10 and 6 microRNAs specifically expressed in BF and in SCM, respectively; 22 microRNAs significantly up-regulated in BF; and 2 significantly up-regulated in SCM. To investigate the role of SCM microRNAs in implantation, we focused on the microRNAs specifically expressed/up-regulated in SCM and absent in blank medium. We deepened our understanding of SCM microRNA's biological role by building a network of miRNA-mRNA interaction within the signalling pathways crucial in embryo implantation success. We demonstrated that BF and SCM contain different sets of microRNAs playing different and unique roles in embryo implantation and development. Finally, we suggest that there is not a single "ideal" technique to identify the most competent embryo, but an integrated approach is needed to obtain informative results on the health of the embryo.

The paper aims to investigate the biological role of microRNAs secreted by preimplantation embryo into the blastocoel fluid and to detect a distinctive molecular signature for identifying embryos with the highest implantation potential. We carried on a multicenter retrospective study involving five European IVF centers. We collected 112 blastocoel fluid samples from embryos on day 5 post-fertilization, cultured individually, along with data on blastocyst grade and embryo transfer outcomes. Using a custom TLDA Array, we compared the expression levels of 89 miRNAs between 33 fluids from high-quality implanted embryos and 30 fluids from high-quality not-implanted embryos. Expression differences were assessed using SAM and t-test. Additionally, correlation and function enrichment analysis and network construction were conducted to identify the biological roles of deregulated microRNAs. We identified six up-regulated microRNAs in the blastocoel fluid from implanted embryos, significantly and positively correlated across all samples (r ≥ 0.7; P ≤ 0.05). They could take part in pluripotency circuits, regulating and being regulated by transcription factors associated with stemness, cell growth, and embryo development. The ROC curve analysis confirmed the potential of these miRNAs as implantation classifiers. The six miRNAs up-regulated in blastocoel fluid from implanted embryos may represent a functional molecular signature for evaluating blastocyst quality and identifying the most competent embryos. Their evaluation associated with non-invasive preimplantation genetic testing, integrating epigenetic and genomic analyses, could enhance implantation grade and allow for identification of the euploid embryo not able to implant.

Can non-invasive aneuploidy detection using nanopore sequencing of spent embryo culture medium (SEM) replace PGT-A of trophectoderm biopsy (TEB) samples? Concordance of 80% for good-quality SEM confirm feasibility of nanopore-sequencing, while low-quality/day-5 samples show reduced concordance. The procedure can complement but not replace other methods. PGT-A increases the chances of identifying a viable embryo, but the invasive biopsy required for PGT-A is technically challenging and may negatively impact embryo viability. The analysis of SEM holds promise for non-invasive PGT-A; however various technical challenges remain, raising concerns about its clinical utility. In this experimental comparative study, the detection of aneuploidy in SEM samples using nanopore sequencing technology is compared to routine PGT-A of TEB samples. A total of 174 SEM samples of day (D) 5, D6 or D7 blastocysts from 41 patients undergoing fertility treatment were analyzed for aneuploidy and compared to PGT-A results of corresponding TEB samples. The study was approved by the Ethic Committee of the Medical University Vienna (EK-1397/2022). For the niPGT-A analysis, SEM samples were amplified using whole genome amplification (WGA) and prepared for nanopore sequencing on the portable MinION sequencing device. A nanopore-specific data analysis pipeline was optimized for automated aneuploidy calling in SEM samples, and the results were compared to routine TEB-based PGT-A using array comparative genomic hybridization (aCGH). Concordance rates were stratified based on multiple criteria to identify conditions that maximize consistency and support potential clinical application of SEM analysis. This is the first experimental study, systematically evaluating nanopore sequencing for aneuploidy analysis using SEM. PGT-A results of both TEB and SEM were successfully generated and compared for 143 embryos (29 D5 and 114 D6/7 samples). Sample-level concordance for D5 samples was significantly lower (51.7%), compared to D6/7 samples, showing concordance rates of 77.2%. For good-quality D6/7 samples, concordance reached 80.4% (82/102 samples concordantly euploid or aneuploid). Sex chromosomes were concordantly detected in 91.6% of all included samples. Although maternal contamination cannot be completely ruled out, no statistically significant evidence was observed, as false-negative euploid, female results were not overrepresented. Among 28 false-negative samples (SEM: euploid, TEB: aneuploid), 13 (46.4%) showed only segmental (6/28, 21%) or mosaic (7/28, 25%) aneuploidies in TEB, suggesting potential uncertainty in embryo status as previously reported. Segmental aneuploidies were accurately identified in 6 SEM samples from cases with known parental translocations. Notably, one segmental aneuploidy linked to a known translocation carrier was detected only in SEM. The reference method aCGH is limited in resolution compared to NGS-based approaches. Additionally, TEB-based PGT-A results in general might not always represent the whole embryo, especially for mosaic and segmental results. Whole blastocyst screening as reference would therefore be ideal, but legally not possible in this study. Concordance rates of 80% for good-quality D6/7 SEM samples compared to invasive TEB samples confirm feasibility of this fast and cost-effective technology. However, reduced concordance in D5/low DNA samples highlights limitations in clinical applicability. Robust validation and methodological adaptations need to be implemented before niPGT-A might replace invasive PGT-A. No

Innerhalb der letzten 10 Jahre hat sich die Uterustransplantation als effektive Methode entwickelt, um Frauen mit absoluter uteriner Infertilität zu einer Schwangerschaft zu verhelfen. Mehr als 70 Frauen wurden seit den ersten Erfolgen in Schweden weltweit transplantiert und mehr als 40 Kinder wurden seither mithilfe dieser Technik geboren. Während neue minimal-invasive Operationstechniken entwickelt wurden, um die Belastung für die Lebendspenderinnen so gering wie möglich zu halten, führen manche Zentren erste Studien an Post-mortem-Spenden von Multiorganspenderinnen durch. Durch die steigende Zahl an Gebärmuttertransplantationen sind mittlerweile typische Komplikationen und Schwangerschaftsverläufe bekannt und werden entsprechend in internationalen Registerdaten publiziert. Mit der international wachsenden Zahl an Uterustransplantationen wird die Frage der Finanzierung dieser kostenintensiven Behandlung immer größer. Gerade in Ländern, in denen die Leihmutterschaft als Therapiealternative verboten ist, plädieren Bioethiker dafür, die Uterustransplantation für betroffene Frauen mit uteriner Infertilität zu ermöglichen. Zusätzlich ergeben sich theoretische Anwendungsgebiete der Uterustransplantation im Bereich der Transgender-Medizin, welche zu einem zusätzlichen Kostenanstieg für das Gesundheitssystem führen könnten.

Background: Progestin-primed ovarian stimulation (PPOS) stimulates ovaries to block the premature surge of luteinizing hormone (LH) by using micronized progesterone or a progestin during the follicular phase instead of the conventional gonadotropin-releasing hormone (GnRH) analogues or GnRH antagonists downregulating LH to obtain multi-follicle engagement. Current work aims to assess the influence of progestogen treatment on ovarian stimulation and the ability to control LH surge, its efficacy and suitability in retrieving oocytes, without affecting the embryo quality and its benefit among infertile women long-term outcomes on children compared to standard stimulation protocols. Materials and Methods: The literature review used the randomized control trials published in the Pubmed database from January 2015 to April 2021. To generate the citation list, the following keywords were used: ‘progestin-primed ovarian stimulation’, ‘PPOS’, ‘micronized progesterone’, ‘medroxyprogesterone’, and/or ‘dydrogesterone’. The selected articles analyzed the cohort, intervention, and scheme of the progestin-primed ovarian stimulation protocol in controlled ovarian stimulation (COS) for in-vitro fertilization (IVF)/intra cytoplasmic sperm injection (ICSI) used in Assisted Reproductive Technologies (ART). Results: Overall we concluded that PPOS for IVF/ICSI in ART results in a higher number of obtained embryos, lower incidence of OHSS, equal duration of stimulation, number of retrieved oocytes, and number of MII oocytes. It is also suggested that long-term safety in children shows no significant difference between the study and control groups. Conclusions: Despite the outcomes of progestin stimulation cycles among all cohorts, we concluded that poor ovarian responders, patients with PCOS, women of advanced age and oocyte donors benefit the most from using PPOS.

Trophectoderm-based preimplantation genetic testing for aneuploidies (PGT-A) is used worldwide as a means of selecting embryos with high potential for achieving a live birth. However, trophectoderm analysis may be impaired through embryonic mosaicism, leading to genetically healthy embryos being falsely discarded, and thus even reducing cumulative live birth rates. Polar body biopsy, a technique applied since the early days of preimplantation testing, has been abandoned by most IVF centres. In comparison to trophectoderm analysis, however, polar body biopsy might even have certain advantages over trophectoderm PGT-A. This Countercurrent contribution discusses the newest clinical evidence, as well as ethical and cost-efficiency considerations, and argue that polar body analysis should be reconsidered.

BACKGROUND:Preimplantation genetic testing for aneuploidy (PGT-A) using polar body (PB) biopsy offers a clinical benefit by reducing the number of embryo transfers and miscarriage rates but is currently not cost-efficient. Nanopore sequencing technology opens possibilities by providing cost-efficient and fast sequencing results with uncomplicated sample preparation work flows.METHODS:In this comparative experimental study, 102 pooled PB samples (99 passing QC) from 20 patients were analyzed for aneuploidy using nanopore sequencing technology and compared with array comparative genomic hybridization (aCGH) results generated as part of the clinical routine. Samples were sequenced on a Nanopore MinION machine. Whole-chromosome copy-numbers were called by custom bioinformatic analysis software. Automatically called results were compared to aCGH results.RESULTS:Overall, 96/99 samples were consistently detected as euploid or aneuploid in both methods (concordance = 97.0%, sensitivity = 0.957, specificity = 1.0, positive predictive value = 1.0, negative predictive value = 0.906). On the chromosomal level, concordance reached 98.7%. Chromosomal aneuploidies analyzed in this trial covered all 23 chromosomes with 98 trisomies, and 97 monosomies in 70 aCGH samples.The whole nanopore work flow is feasible in under 5 h (for one sample) with a maximum time of 16 h (for 12 samples), enabling fresh PB-euploid embryo transfer. A material cost of US$ 165 (EUR 150)/sample possibly enables cost-efficient aneuploidy screening.CONCLUSIONS:This is the first study systematically comparing nanopore sequencing with standard methods for the detection of PB aneuploidy. High concordance rates confirmed the feasibility of nanopore technology for this application. Additionally, the fast and cost-efficient work flow reveals the clinical utility of this technology, making it clinically attractive for PB PGT-A.

Purpose To assess early embryonic developmental potential of embryos affected by maternally inherited meiotic aneuploidies. Methods This observational, descriptive study includes 930 oocytes from 151 patients which were retrospectively analyzed by combining the morphological assessment with the genetic results from polar body diagnosis. Results Of 930 oocytes examined, 566 (60.9%) were tested aneuploid. Developmental potential until cleavage stage was not affected by trisomies or monosomies (69.6% vs. 77.1%, p = 0.75). However, trisomies significantly more often resulted in top quality cleavage stage embryos compared to monosomies (20% vs. 17.6%, p = < 0.01). Top quality blastocysts were more likely to be euploid than aneuploid (52.4% vs. 47.6%, p = 0.032). Additionally, significantly more aneuploid embryos resulted in developmental arrest compared to euploid embryos (15.3% vs. 6.7%, p = 0.003). Overall, there was no significant difference in the frequency of trisomies and monosomies in blastocyst stage embryos. (28.3% vs. 28.2%; p = 0.81). In contrast to earlier developmental stages, distribution of trisomies and monosomies did not differ in top quality blastocysts (8.3% vs. 5.3%, p = 0.32). However, certain chromosomal abnormalities showed a higher potential to develop into a top-rated blastocyst. These included monosomies 2, 5, 8, 10, 16, 17, 20, 21, and 22 and trisomies 2, 4, 5, 8, 9, 10, 11, 12, 13, 16, 17, 18 and 20. Conclusion Meiotically induced maternal aneuploidies have different effects on early embryonic development. While no difference in developmental potential between monosomies and trisomies could be observed in blastocysts, cleavage stage quality was significantly affected by chromosomal aneuploidies.

IntroductionWomen with migration background present specific challenges related to risk stratification and care of gestational diabetes mellitus (GDM). Therefore, this study aims to investigate the role of ethnic origin on the risk of developing GDM in a multiethnic European cohort.MethodsPregnant women were included at a median gestational age of 12.9 weeks and assigned to the geographical regions of origin: Caucasian Europe (n = 731), Middle East and North Africa countries (MENA, n = 195), Asia (n = 127) and Sub-Saharan Africa (SSA, n = 48). At the time of recruitment maternal characteristics, glucometabolic parameters and dietary habits were assessed. An oral glucose tolerance test was performed in mid-gestation for GDM diagnosis.ResultsMothers with Caucasian ancestry were older and had higher blood pressure and an adverse lipoprotein profile as compared to non-Caucasian mothers, whereas non-Caucasian women (especially those from MENA countries) had a higher BMI and were more insulin resistant. Moreover, we found distinct dietary habits. Non-Caucasian mothers, especially those from MENA and Asian countries, had increased incidence of GDM as compared to the Caucasian population (OR 1.87, 95%CI 1.40 to 2.52, p < 0.001). Early gestational fasting glucose and insulin sensitivity were consistent risk factors across different ethnic populations, however, pregestational BMI was of particular importance in Asian mothers.DiscussionPrevalence of GDM was higher among women from MENA and Asian countries, who already showed adverse glucometabolic profiles at early gestation. Fasting glucose and early gestational insulin resistance (as well as higher BMI in women from Asia) were identified as important risk factors in Caucasian and non-Caucasian patients.

Recently, 2 branches of the wide area of synthetic biology-in vitro gametogenesis and synthetic embryo development-have gained considerable attention. Rodent induced pluripotent stem cells derived via reprogramming of somatic cells can in vitro be differentiated into gametes to produce fertile offspring. And even synthetic embryos with organ progenitors were generated ex utero entirely from murine pluripotent stem cells. The use of these approaches in basic research, which is rightfully accompanied by an ethical discussion, will allow hitherto unattainable insights into the processes of the beginning of life. There is a broad international consensus that currently the application of these technologies in human-assisted reproduction must be considered to be unsafe and unethical. However, newspaper headlines also addressed the putatively resulting paradigm shift in human reproduction and thereby raised expectations in patients. Due to unsolved biological and technological obstacles, most scientists do not anticipate translation of any of these approaches into human reproductive medicine, if ever, for the next 10 years. Still, whereas the usage of synthetic embryos for reproductive purposes should be banned, in the context of in vitro-derived human gametes it is not too early to initiate the evaluation of the ethical implications, which could still remain assuming all technological hurdles can ever be cleared.

Bariatric surgery confers potential advantages for obese patients, but also risks for pregnancy. Perinatal outcomes may be varying between surgical procedures. This topic was recently addressed by a systematic review in BMC Pregnancy and Childbirth. This commentary will discuss the scientific background and implications for future research.

Due to the limited accessibility of the in vivo situation, the scarcity of the human tissue, legal constraints, and ethical considerations, the underlying molecular mechanisms of disorders, such as preeclampsia, the pathological consequences of fetomaternal microchimerism, or infertility, are still not fully understood. And although substantial progress has already been made, the therapeutic strategies for reproductive system diseases are still facing limitations. In the recent years, it became more and more evident that stem cells are powerful tools for basic research in human reproduction and stem cell-based approaches moved into the center of endeavors to establish new clinical concepts. Multipotent fetal stem cells derived from the amniotic fluid, amniotic membrane, chorion leave, Wharton´s jelly, or placenta came to the fore because they are easy to acquire, are not associated with ethical concerns or covered by strict legal restrictions, and can be banked for autologous utilization later in life. Compared to adult stem cells, they exhibit a significantly higher differentiation potential and are much easier to propagate in vitro. Compared to pluripotent stem cells, they harbor less mutations, are not tumorigenic, and exhibit low immunogenicity. Studies on multipotent fetal stem cells can be invaluable to gain knowledge on the development of dysfunctional fetal cell types, to characterize the fetal stem cells migrating into the body of a pregnant woman in the context of fetomaternal microchimerism, and to obtain a more comprehensive picture of germ cell development in the course of in vitro differentiation experiments. The in vivo transplantation of fetal stem cells or their paracrine factors can mediate therapeutic effects in preeclampsia and can restore reproductive organ functions. Together with the use of fetal stem cell-derived gametes, such strategies could once help individuals, who do not develop functional gametes, to conceive genetically related children. Although there is still a long way to go, these developments regarding the usage of multipotent fetal stem cells in the clinic should continuously be accompanied by a wide and detailed ethical discussion.

The aim of this pre-clinical study is to determine whether nanopore sequencing-based analysis of embryonic cell-free DNA (cfDNA) in spent blastocyst culture medium is feasible and represents an alternative to routine preimplantation genetic testing for aneuploidy (PGT-A). To investigate the concordance of embryonic cfDNA with trophectoderm biopsies (TE) from the same embryo a total of 100 blastocysts from 30 patients are included in this ongoing pre-clinical study. Whole genome amplification was performed from day-6/7 blastocysts culture media samples together with negative controls and were prepared for sequencing by end-prepping, barcoding and adapter ligation. Samples were pooled equimolar for sequencing on a Oxford Nanopore Technologies (ONT) MinION device and were sequenced for around 60 minutes/sample. Copy-numbers were called by a custom bioinformatic analysis software after alignment and pre-processing. Automatically called results were compared to TE samples that were analyzed using array comparative genomic hybridization (aCGH) for routine PGT-A. This pre-clincial study was approved by the ethical committee of the Medical University of Vienna, all patients provided written informed consent. At the time of submission, 46 samples had been processed, including 16 euploid and 30 aneuploid samples. 2 aCGH and 1 nanopore sequencing samples were excluded due to unclear results. Compared to TE-aCGH, Nanopore cfDNA sequencing identified 35 out of 46 samples correctly as euploid or aneuploid (concordance = 76%, specificity = 0.750, sensitivity = 0.767, PPV = 0.852, NPV = 0.750). Ploidy discordance between TE and embryo cfDNA mainly occurred in samples that were classified as aneuploid by TE aCGH due to detected mosaicism or samples automatically classified as aneuploid by ONT due to detected segmental aneuploidies. ONT correctly distinguished normal embryos from reciprocal translocation carrier embryos obtained from 2 translocation patients included in this study. The first results of this pre-clinical study showed that ploidy evaluation on blastocyst culture medium based on ONT seems feasible. Concordance rates confirmed feasibility of nanopore technology for this application and the fast and cost-efficient sequencing technique shows the potential to provide accessible and comprehensive information of embryo ploidy. Culture media contamination, however, needs to be considered and derived euploid results interpreted with caution.After sequencing of all 100 samples a detailed evaluation will be carried out to confirm these results and investigate diagnostic accuracy of this technique.

Abstract Study question Is long-read nanopore sequencing feasible and reproducible as routine technique for aneuploidy detection, potentially allowing fresh embryo transfer PGT-A cycles? Summary answer Pre-clinical analysis of euploid and aneuploid DNA and single cells using long-read nanopore sequencing resulted in high concordance and reproducible results for aneuploidy detection. What is known already PGT-A is mostly performed using short-read next-generation sequencing, which requires high initial investment costs and high running expenses. Third-generation sequencing is a novel sequencing technology with the potential of fast, easy, and cost-effective sequencing analysis, possible even for small and less well-financed clinics. Long-read nanopore sequencing for PGT was mainly shown for structural variants and monogenetic disease, which comes with high costs and is far from clinical routine. PGT-A from trophectoderm biopsy samples using nanopore sequencing was so far demonstrated in a small pilot study and further pre-clinical and clinical studies are needed to transfer the technology into clinical routine. Study design, size, duration In this pre-clinical study, euploid and aneuploid DNA and single cells, as well as three to 20 cells were analyzed for aneuploidy using two different whole genome amplification (WGA) kits and long-read nanopore sequencing. In total, 44 different samples were analyzed after multiple displacement amplification (MDA) using REPLIg WGA kit (QIAGEN) and so far, 15 samples were analyzed using PicoPlex WGA kit (Takara) from April 2021. To confirm reproducibility, certain WGA samples were sequenced repetitively. Participants/materials, setting, methods Different euploid and aneuploid gDNA samples were diluted to 4.5 pg DNA per sample. Four different human fibroblast cell lines were diluted to approx. 20 cells, or single cells/three cells were picked using micromanipulation technique. DNA and cells were amplified, prepared for sequencing, and sequenced on MinION sequencer from Oxford Nanopore Technology. Data were analyzed using a custom pipeline consisting of pre-processing, alignment and copy-number calling. QC values and whole chromosome aneuploidies were determined automatically. Main results and the role of chance From 44 different single cells (n = 14), few cells (n = 9) or diluted gDNA (n = 21) samples amplified using MDA, 42 samples showed good quality sequencing results. Two samples result in QC failure, yielding a sample-success-rate (SSR) of 95.5%. Overall, sample sensitivity was 100%, specificity 95.2% with positive predictive value (PPV) of 95.5% and negative predictive value (NPV) of 100%. Per chromosome sensitivity was 100%, specificity 99.8% with PPV of 93.3% and NPV of 100%. Using PicoPlex WGA, 15 samples were analyzed so far: 7 gDNA and 8 single cell samples. The study is ongoing. All samples analyzed resulted in high quality sequencing data with the correct karyotype, leading to 100% SSR, 100% sensitivity, specificity, PPV, NPV per samples as well as per chromosome. Repetitive sequencing (n = 3) of four MDA amplified single cells showed identical sequencing results, indicating high reproducibility of library preparation, and sequencing. A 5p deletion in one cell line was correctly identified in all single cell analyses from either MDA or PicoPlex amplification, indicating sufficient resolution even for segmental aneuploidies. The whole workflow is feasible in under 24 hours. These results indicate high accuracy and high reproducibility of nanopore sequencing technology for single cell aneuploidy detection, possibly transferable for PGT-A. Limitations, reasons for caution The results of this pre-clinical study look very promising and workflow for sample preparation, sequencing and data analysis is fast, cost-efficient, and feasible for PGT-A applications. Nevertheless, no polar body, blastomere or trophectoderm biopsy sample was used and a clinical trial using real clinical samples is needed to confirm applicability. Wider implications of the findings Implementing novel technologies into clinical routine requires extensive systematic pre-clinical and clinical testing. To our knowledge, this is the first study that systematically analyzes sensitivity, specificity, PPV and NPV for aneuploidy detection using long-read sequencing technology. The fast workflow principally allows day 3/5 fresh embryo transfer after polar body biopsy. Trial registration number Not applicable

Einleitung Bei konventionellen IVF/ICSI-Zyklen werden die Embryos für den Transfer nach morphologischen Parametern wie Blastozystenausdehnung, Zellzahl und Fragmentierungsrate ausgewählt. Embryonen, die im Blastozystenstadium in allen morphologischen Parametern eine optimale Entwicklung aufweisen, werden als Top-Embryos bezeichnet und gelten als geeignet für den Transfer in utero. Ziel dieser Studie ist es, den morphologischen Entwicklungsstatus von aneuploiden Embryonen an Tag 3 und Tag 5 post-Fertilisation nach chromosomaler Fehlverteilung zu vergleichen. Die primäre Studienfrage ist, welche aneuploiden Konstellationen die Möglichkeit und das Potential haben, sich trotz Fehlverteilung zu einer morphologischen Top-Blastozyste zu entwickeln.

Introduction: Previous studies demonstrated a continuous decline in fetal growth throughout singleton pregnancy after bariatric surgery. However, intrauterine growth in twin pregnancy is subjected to further underlying processes. This study was to investigate the longitudinal assessment of fetal biometry and abdominal fat thickness of twin pregnancies conceived after gastric bypass (GB) surgery and compare them to body mass index-matched (BMIM) and obese (OB) controls. Materials and Methods: We retrospectively assessed ultrasound data of 30 women with dichorionic-diamniotic twin pregnancy (11 women after GB surgery, 9 OB mothers with pregestational BMI ≥30 kg/m2, and 10 BMIM and age-matched controls). We assessed fetal growth parameters including fetal subcutaneous adipose tissue thickness (FSCTT) as well as newborn biometry after delivery. Patient characteristics were obtained from the medical records. Results: The rise in FSCTT curves was markedly slower in the twin offspring of women with history of GB as compared to the offspring of OB mothers and offspring of BMIM controls. Hence, FSCTT was significantly decreased in the GB offspring as compared to both control groups at 34 weeks of gestation. Also, growth curves of abdominal circumference were decreased in the offspring of GB patients as compared to OB mothers. Infants of mothers with history of GB showed significantly lower birth weight percentiles compared to newborns of OB mothers (27.2 vs. 48.8 pct, p = 0.025). There was no significant difference in inter-twin birth weight difference between the offspring of GB (median: 9.9%, interquartile ranges [IQR]: 6.5–20.0) versus OB (median: 14.6%, IQR: 8.2–21.6) and BMIM controls (median: 9.0%, IQR: 6.3–12.6, p = 0.714). Conclusions: In summary, intrauterine growth delay in twin pregnancies after GB is assumed to be a multifactorial event with altered metabolism as the most important factor. However, special attention must be paid to the particularity of twin pregnancies as they seem to be subject to other additional mechanism.

OBJECTIVE:To provide a video tutorial on vaginal transisthmic myomectomy in women with large submucosal fibroids. DESIGN:Stepwise demonstration of the technique, with a narrated video footage. SETTING:Submucosal fibroids protrude into the uterine cavity and can cause numerous symptoms, including abnormal uterine bleeding, dysmenorrhea, subfertility, and obstetric complications. Over the last decades, hysteroscopic resection has become the preferred surgical approach for submucosal fibroids because it provides significant advantages regarding perioperative morbidity and postoperative recovery time when compared with laparotomy or laparoscopy with complete transection of the uterine wall. However, in large or multiple fibroids, longer surgery durations of hysteroscopic resection can lead to higher complication rates and incomplete resection. In some cases, hysteroscopic resection might even be impossible to perform. Furthermore, in many regions, special equipment for hysteroscopic myomectomy might not be available. Herein, we present a minimally invasive surgical alternative for approaching submucosal fibroids. PATIENT(S):A 26-year-old woman presenting with hypermenorrhea and dysmenorrhea (on a numeric rating scale from 0-10) caused by a recurrent International Federation of Gynaecology and Obstetrics (FIGO) type 0 fibroid measuring 5 cm in diameter. INTERVENTION(S):Vaginal transisthmic myomectomy performed with a longitudinal transection of the uterine cervix and isthmus, morcellation of the fibroid with a scalpel, and multilayer reconstruction. MAIN OUTCOME MEASURE(S):Vaginal transisthmic myomectomy is a fast and relatively simple, minimally invasive surgical technique suitable for large or multiple FIGO 0 and some FIGO 1 fibroids, necessitating the use of only basic surgical equipment. RESULT(S):Vaginal transisthmic myomectomy provides an additional minimally invasive surgical approach for submucosal fibroids. CONCLUSION(S):This surgical option for selected patients may help prevent complications resulting from prolonged hysteroscopic surgery, repeated hysteroscopic procedures owing to incomplete resection, and the morbidity of transabdominal approaches for myomectomy. With this video, we aim to expedite the clinical learning curve of this technique, which should be investigated on a broader scale in the future.

RESEARCH QUESTION:Full-length 16S rRNA gene sequencing using nanopore technology is a fast alternative to conventional short-read 16S rRNA gene sequencing with low initial investment costs that has been used for various microbiome studies but has not yet been investigated as an alternative approach for endometrial microbiome analysis. Is in-situ 16S rRNA gene long-read sequencing using portable nanopore sequencing technology feasible and reliable for endometrial microbiome analysis?DESIGN:A prospective experimental study based on 33 patients seeking infertility treatment between January and October 2019. A 16S rRNA gene long-read nanopore sequencing protocol for analysing endometrial microbiome samples was established, including negative controls for contamination evaluation and positive controls for bias evaluation. Contamination caused by kit and exterior sources was identified and excluded from the analysis. Endometrial samples from 33 infertile patients were sequenced using the optimized long-read nanopore sequencing protocol and compared with conventional short-read sequencing carried out by external laboratories.RESULTS:Of the 33 endometrial patient samples, 23 successfully amplified (69.7%) and their microbiome was assessed using nanopore sequencing. Of those 23 samples, 14 (60.9%) were Lactobacillus-dominated (>80% of reads mapping to Lactobacillus), with 10 samples resulting in more than 90% Lactobacillus reads. Our long-read nanopore sequencing revealed results similar to two conventional short-read sequencing approaches and to long-read sequencing validation carried out in external laboratories.CONCLUSION:In this pilot study, 16S rRNA gene long-read nanopore sequencing was established to analyse the endometrial microbiome in situ that could be widely applied owing to its cost efficiency and portable character.

The transplantation of endocrine organs can be regarded as the oldest form of transplantation in modern medical history. By the end of the nineteenth and beginning of the twentieth centuries, a large research focus was set on endocrine transplantations. Before the complex endocrine secretion and function was even understood, researchers attempted to cure endocrine diseases and infertility through transplantation of the endocrine glands and gonads. Hence, most endocrine organs have been transplanted in that period, including the thyroid [1], the adrenal gland [2], the testis [3] and the ovary [4]. Even though the principles of transplant rejection have not been understood at that time, researchers already noticed successful transplantations almost exclusively in experiments with autografts. The first published allogeneic ovarian transplantations in animals have been performed by Paul Bert in the sixties of the nineteenth century [5].