Failure to detect DNA in blastocoel fluid is associated with a higher live birth rate in both PGT-A and conventional IVF/ICSI cycles.

Study Question: Is the presence of DNA in the blastocoel fluid (BF) of expanded blastocysts, assessed by whole genome amplification (WGA), associated with the clinical outcome at the first transfer?

Summary Answer: At the first transfer, blastocysts with negative BF-WGA have more chance to implant and to develop to term than those with positive BF-WGA results, both in preimplantation genetic testing for aneuploidies (PGT-A) cycles (where only euploid blastocysts resulting from the chromosomal analysis of trophectoderm (TE) biopsies were transferred) and in IVF/ICSI conventional cycles.

What Is Known Already: Retrospective studies conducted in patients undergoing PGT-A have shown that the incidence of negative BF-WGA was significantly higher in TE-euploid blastocysts than in TE-aneuploid blastocysts. In addition, after the transfer of TE-euploid blastocysts, the ongoing clinical pregnancy rate was significantly higher in the group with negative BF-WGA compared with those with positive BF-WGA.

Birefringence properties of human immotile spermatozoa and ICSI outcome.

Research Question: In sperm samples with complete asthenozoospermia, pregnancies are achieved by intracytoplasmic sperm injection (ICSI), but this condition has a negative impact on fertilization and embryo development owing to the difficulty of identifying viable cells for oocyte injection. Is the selection of sperm cells with head birefringence properties under polarizing light a successful strategy to identify viable spermatozoa?

Design: This study included 192 ICSI cycles with complete asthenozoospermia (83 ejaculated and 109 testicular samples) performed under polarized light. Two types of sperm head birefringence were distinguished: partial (presumably reacted spermatozoa) and total (presumably intact acrosome).

IVF Lite: a smart IVF programme based on mild ovarian stimulation for good prognosis patients.

Research Question: The IVF Lite programme is based on mild ovarian stimulation including up to three fresh/frozen embryo transfers within 12 months. Is it effective and safe in good prognosis patients?

Design: Single-centre prospective study on infertile patients at their first IVF attempt (female age ≤38 years, anti-Müllerian hormone concentrations >1.5 ng/ml and/or FSH ≤10 mIU/ml).

Oocyte donation: not all oocyte cryobanks are the same.

Research Question: Is the efficacy of imported vitrified oocyte donation affected by the cryobank of origin?

Design: Longitudinal cohort study, including 249 completed oocyte warming cycles from 200 recipients (January 2016-July 2020). No severe male factor was included. Vitrified oocytes were provided by three Spanish cryobanks.

Identification of a targetable KRAS-mutant epithelial population in non-small cell lung cancer.

Lung cancer is the leading cause of cancer deaths. Tumor heterogeneity, which hampers development of targeted therapies, was herein deconvoluted via single cell RNA sequencing in aggressive human adenocarcinomas (carrying Kras-mutations) and comparable murine model. We identified a tumor-specific, mutant-KRAS-associated subpopulation which is conserved in both human and murine lung cancer.

Sperm chromosome abnormalities in patients with normal karyotype and in translocation carriers: clinical relevance for assisted reproductive technology.

Research Question: What is the proportion of chromosomally abnormal spermatozoa in men with a history of reproductive failure, including patients with normal karyotype and carriers of translocations? Should this analysis be included in a clinical setting to define the best treatment options for infertile couples?

Design: Aneuploidy for chromosomes XY, 13, 15, 16, 17, 18, 21, 22 was tested by fluorescent in-situ hybridization (FISH) in 1665 samples from couples with normal karyotype having had at least three previous IVF failures, miscarriages, or both (group-A). A FISH test was also carried out in 76 samples from carriers of translocations (group B) to detect the proportion of spermatozoa with unbalanced rearrangement.

Results: In group A, the lowest incidence of aneuploid sperm cells was found in men with normozoospermia (1.

ESHRE Clinical Embryologist certification: the first 10 years.

Study Question: What has the ESHRE programme 'ESHRE Certification for Clinical Embryologists' achieved after 10 years?

Summary Answer: The post-exam analysis showed a pass rate of 60% for Clinical and 50% for Senior Clinical Embryologists and a high level of internal consistency of all exams, leading to a total of 773 certified Clinical and 493 Senior Clinical Embryologists over the decade.

What Is Known Already: In an ESHRE survey on the educational and professional status of Clinical Embryology in Europe, it was found that education of laboratory personnel working in the field of assisted reproduction is highly variable between countries. In 2008, ESHRE introduced a programme, curriculum and certification in the field of Clinical Embryology.

Permanence of de novo segmental aneuploidy in sequential embryo biopsies.

Study Question: Is de novo segmental aneuploidy (SA) a biological event or an artifact that is erroneously interpreted as partial chromosome imbalance?

Summary Answer: The detection of de novo SA in sequential biopsies of preimplantation embryos supports the biological nature of SA.

What Is Known Already: Although some SAs are detected in oocytes and in blastocysts, the highest incidence is observed in cleavage-stage embryos. Based on these findings, we can postulate that the majority of cells affected by SAs are eliminated by apoptosis or that affected embryos mainly undergo developmental arrest.

The Role of Prep1 in the Regulation of Mesenchymal Stromal Cells.

Molecular mechanisms governing cell fate decision events in bone marrow mesenchymal stromal cells (MSC) are still poorly understood. Herein, we investigated the homeobox gene as a candidate regulatory molecule, by adopting hypomorphic mice as a model to investigate the effects of downregulation, using in vitro and in vivo assays, including the innovative single cell RNA sequencing technology. Taken together, our findings indicate that low levels of are associated to enhanced adipogenesis and a concomitant reduced osteogenesis in the bone marrow, suggesting Prep1 as a potential regulator of the adipo-osteogenic differentiation of mesenchymal stromal cells.

Deoxyribonucleic acid detection in blastocoelic fluid: a new predictor of embryo ploidy and viable pregnancy.

Objective: To investigate blastocysts, defined as euploid and aneuploid by trophectoderm (TE) cell analysis, for the presence of DNA in the blastocoelic fluid (BF) detected by whole-genomic amplification (WGA); and to correlate the presence of DNA in BF with the clinical outcome after the transfer of TE-euploid blastocysts.

Design: Retrospective study.

Setting: In vitro fertilization unit.

Preimplantation genetic testing for aneuploidy by microarray analysis of polar bodies in advanced maternal age: a randomized clinical trial.

Study Question: Does preimplantation genetic testing for aneuploidy (PGT-A) by comprehensive chromosome screening (CCS) of the first and second polar body to select embryos for transfer increase the likelihood of a live birth within 1 year in advanced maternal age women aged 36-40 years planning an ICSI cycle, compared to ICSI without chromosome analysis?

Summary Answer: PGT-A by CCS in the first and second polar body to select euploid embryos for transfer does not substantially increase the live birth rate in women aged 36-40 years.

What Is Known Already: PGT-A has been used widely to select embryos for transfer in ICSI treatment, with the aim of improving treatment effectiveness. Whether PGT-A improves ICSI outcomes and is beneficial to the patients has remained controversial.

Prep1 prevents premature adipogenesis of mesenchymal progenitors.

Transcriptional regulators are crucial in adipocyte differentiation. We now show that the homeodomain-containing transcription factor Prep1 is a repressor of adipogenic differentiation since its down-regulation (DR) in both ex vivo bone marrow-derived mesenchymal stromal cells (MSC) and in vitro 3T3-L1 preadipocytes significantly increases their adipogenic differentiation ability. Prep1 acts at a stage preceding the activation of the differentiation machinery because its DR makes cells more prone to adipogenic differentiation even in the absence of the adipogenic inducers.

PGD for the m.14487 T>C mitochondrial DNA mutation resulted in the birth of a healthy boy.

We report on the first PGD performed for the m.14487 T>C mitochondrial DNA (mtDNA) mutation in the MT-ND6 gene, associated with Leigh syndrome. The female carrier gave birth to a healthy baby boy at age 42.

Current regulatory arrangements for assisted conception treatment in European countries.

Infertility is a condition affecting an increasing number of individuals all over the world. In recent years, this phenomenon has spread across both western countries and developing countries, thus developing the features of a pandemic. For this reason, the World Health Organization (WHO) acknowledged that infertility should be considered a disease to all intents and purposes, as it diminishes the health and wellbeing of the individuals who suffers from it.

No need for luteal phase support in IVF cycles after mild stimulation: proof-of-concept study.

This is a pilot study performed in a private IVF unit. The objective of the study was to investigate whether luteal support is required in IVF cycles after mild stimulation with clomiphene citrate and low FSH doses. The study included 15 patients with good prognosis (defined as ≤38 years old with normal ovarian reserve and normovulatory cycles, body mass index <29 kg/m, no previous cycles, no severe endometriosis, no history of recurrent miscarriage, no endocrine/autoimmune diseases and no surgical semen extraction from the partner) undergoing IVF with mild stimulation.

Time to take human embryo culture seriously.

Study Question: Is it important that end-users know the composition of human embryo culture media?

Summary Answer: We argue that there is as strong case for full transparency concerning the composition of embryo culture media intended for human use.

What Is Known Already: Published data suggest that the composition of embryo culture media may influence the phenotype of the offspring.

Study Design, Size, Duration: A review of the literature was carried out.

Targeted BMI1 inhibition impairs tumor growth in lung adenocarcinomas with low CEBPα expression.

Lung cancer is the most common cause of cancer deaths. The expression of the transcription factor C/EBPα (CCAAT/enhancer binding protein α) is frequently lost in non-small cell lung cancer, but the mechanisms by which C/EBPα suppresses tumor formation are not fully understood. In addition, no pharmacological therapy is available to specifically target C/EBPα expression.

Preimplantation genetic testing: polar bodies, blastomeres, trophectoderm cells, or blastocoelic fluid?

Objective: To investigate the blastocoelic fluid (BF) for the presence of DNA that could be amplified and analyzed; the extent to which its chromosomal status corresponds to that found in trophectoderm (TE) cells, polar bodies (PBs), or blastomeres; and the identification of segmental abnormalities.

Design: Longitudinal cohort study.

Setting: In vitro fertilization unit.

The educational and professional status of clinical embryology and clinical embryologists in Europe.

Study Question: What is the recognition of clinical embryology and the current status of clinical embryologists in European countries, regarding educational levels, responsibilities and workload, and need for a formal education in assisted reproductive technology (ART)?

Summary Answer: It is striking that the profession of clinical embryology, almost 40 years after the introduction of IVF, is still not officially recognized in most European countries.

What Is Known Already: Reproductive medicine has developed into a sophisticated multidisciplinary medical branch since the birth of Louise Brown 37 years ago. The European Board & College of Obstetrics and Gynaecology (EBCOG) has recognized reproductive medicine as a subspeciality and has developed a subspeciality training for gynaecologists in collaboration with the European Society for Human Reproduction and Embryology (ESHRE).