Clinical pregnancy rates after blastocyst culture at a stable temperature of 36.6°C versus 37.1°C: a prospective randomized controlled trial.

Study Question: Is there a difference in clinical pregnancy rates (CPRs) in good prognosis patients after single embryo transfer (SET) on Day 5, in case of stable culture at 36.6°C or 37.1°C?

Summary Answer: CPR (with heartbeat at 7 weeks) after blastocyst transfer do not differ after culturing at 36.

Optimized sperm selection: a highly efficient device for the isolation of progressive motile sperm with low DNA fragmentation index.

Purpose: To identify the sperm preparation procedure that selects the best sperm population for medically assisted reproduction.

Methods: Prospective observational study comparing the effect of four different sperm selection procedures on various semen parameters. Unused raw semen after routine diagnostic analysis was split in four fractions and processed by four different methods: (1) density gradient centrifugation (DGC), (2) sperm wash (SW), (3) DGC followed by magnetic activated cell sorting (MACS), and (4) using a sperm separation device (SSD).

Ovarian Tissue Oocyte-In Vitro Maturation for Fertility Preservation.

Mature oocyte vitrification is the standard of care to preserve fertility in women at risk of infertility. However, ovarian tissue cryopreservation (OTC) is still the only option to preserve fertility in women who need to start gonadotoxic treatment urgently or in prepubertal children. During ovarian cortex preparation for cryopreservation, medullar tissue is removed.

Does dual oocyte retrieval with continuous FSH administration increase the number of mature oocytes in low responders? An open-label randomized controlled trial.

Study Question: Is there an increase in the total number of metaphase II (MII) oocytes between a conventional ovarian stimulation (OS) and a double uninterrupted stimulation?

Summary Answer: There is no increase in the total number of MII oocytes when comparing one conventional OS to a continuous stimulation with double oocyte aspiration.

What Is Known Already: Based on the concept of multiple follicular waves, the combination of two stimulations in the same ovarian cycle has gained interest in patients with a low ovarian reserve. This so-called dual stimulation approach is usually characterized by a discontinuation of FSH administration for ∼5 days and appears to have a favourable impact on the number of retrieved oocytes without affecting the embryo quality or ploidy status.

Enzymatic tissue processing after testicular biopsy in non-obstructive azoospermia enhances sperm retrieval.

Study Question: What is the added value of enzymatic processing of testicular biopsies on testicular sperm retrieval (SR) rates for patients with non-obstructive azoospermia (NOA)?

Summary Answer: In addition to mechanical mincing, enzymatic digestion increased SR rates in testicular biopsies of NOA patients.

What Is Known Already: Many studies focus on the surgical approach to optimize recovery of testicular sperm in NOA, and in spite of that, controversy still exists about whether the type of surgery makes any difference as long as multiple biopsies are taken. Few studies, however, focus on the role of the IVF laboratory and the benefit of additional lab procedures, e.

Selecting active matter according to motility in an acoustofluidic setup: self-propelled particles and sperm cells.

Active systems - including sperm cells, living organisms like bacteria, fish, birds, or active soft matter systems like synthetic "microswimmers" - are characterized by motility, , the ability to propel using their own "engine". Motility is the key feature that distinguishes active systems from passive or externally driven systems. In a large ensemble, motility of individual species can vary in a wide range.

Spermatogenesis after gonadotoxic childhood treatment: follow-up of 12 patients.

Study Question: What is the long-term impact of presumed gonadotoxic treatment during childhood on the patient's testicular function at adulthood?

Summary Answer: Although most patients showed low testicular volumes and some degree of reproductive hormone disruption 12.3 (2.3-21.

Electronic witnessing in the medically assisted reproduction laboratory: insights and considerations after 10 years of use.

Study Question: What have we learnt after 10 years of electronic witnessing?

Summary Answer: When applied correctly, an electronic witnessing system can replace manual witnessing in the medically assisted reproduction lab to prevent sample mix-up.

What Is Known Already: Electronic witnessing systems have been implemented to improve the correct identification, processing, and traceability of biological materials. When non-matching samples are simultaneously present in a single workstation, a mismatch event is generated to prevent sample mix-up.

Effect of A23187 ionophore treatment on human blastocyst development-a sibling oocyte study.

Purpose: To investigate whether treatment with commercially available ready-to-use A23187 ionophore (GM508-CultActive) improves embryo development outcome in patients with a history of embryo developmental problems.

Methods: This is a uni-center prospective study in which sibling oocytes of patients with embryos of poor quality on day 5 in the previous cycle were treated or not with CultActive.

Results: Two hundred forty-seven metaphase II (MII) oocytes from 19 cycles performed between 2016 and 2019 were included in the study.

Combining fertility preservation procedures to spread the eggs across different baskets: a feasibility study.

Study Question: What is the reproductive potential following combinations of ovarian stimulation, IVM and ovarian tissue cryopreservation (OTC) in female patients seeking fertility preservation (FP)?

Summary Answer: In selected patients, combining different FP procedures is a feasible approach and reproductive outcomes after FP in patients who return to attempt pregnancy are promising.

What Is Known Already: FP is increasingly performed in fertility clinics but an algorithm to select the most suitable FP procedure according to patient characteristics and available timeframe is currently lacking. Vitrification of mature oocytes (OV) and OTC are most commonly performed, although in some clinical scenarios a combination of procedures including IVM, to spread the sources of gametes, may be considered in order to enhance reproductive options for the future.

Live births following fertility preservation using in-vitro maturation of ovarian tissue oocytes.

Study Question: Can oocytes extracted from excised ovarian tissue and matured in vitro be a useful adjunct for urgent fertility preservation (FP)?

Summary Answer: Ovarian tissue oocyte in-vitro maturation (OTO-IVM) in combination with ovarian tissue cryopreservation (OTC) is a valuable adjunct technique for FP.

What Is Known Already: Despite the impressive progress in the field, options for FP for cancer patients are still limited and, depending on the technique, clinical outcome data are still scarce.

Study Design, Size, Duration: This was a retrospective cohort study conducted at a university hospital-affiliated fertility clinic between January 2012 and May 2019.

When does germ cell loss and fibrosis occur in patients with Klinefelter syndrome?

Study Question: When does germ cell loss and fibrosis occur in patients with Klinefelter syndrome (KS)?

Summary Answer: In KS, germ cell loss is not observed in testicular tissue from fetuses in the second semester of pregnancy but present at a prepubertal age when the testicular architecture is still normal, while fibrosis is highly present at an adolescent age.

What Is Known Already: Most KS patients are azoospermic at adult age because of a massive germ cell loss. However, the timing when this germ cell loss starts is not known.

Obstetric and neonatal outcome following ICSI with assisted oocyte activation by calcium ionophore treatment.

Purpose: Calcium ionophore treatment is being used in assisted reproductive technology (ART) for cases with previous low fertilization rate or total absence of fertilization after insemination by intracytoplasmic sperm injection or when a specific indication such as globozoospermia is present. As this technique is more invasive and differs from the physiological process of fertilization, a thorough investigation of the health of the children born following this procedure is required. We intent to report the medical outcome of all children conceived following calcium ionophore treatment in our IVF center.

Do ARTs affect the incidence of monozygotic twinning?

Study Question: Does the manipulation of gametes or embryos during ARTs increase the risk for monozygotic twinning (MZT)?

Summary Answer: Frozen embryo transfer (ET) is associated with a lower MZT rate, while blastocyst culture is associated with an increased risk of monozygotic pregnancy.

What Is Known Already: Monozygotic twins have a higher risk for perinatal complications. Although an increased incidence of monozygotic pregnancies after ART has been previously reported, data regarding the possible impact of different laboratory procedures are conflicting.

Reduced blastocyst formation in reduced culture volume.

Purpose: The aim of this prospective sibling oocyte study was to evaluate whether reduced culture volume improves blastocyst formation.

Methods: Twenty-three patients with extended embryo culture until day 5 were selected for the study. After injection, 345 sibling oocytes were individually cultured in either 25 or 7 μl droplets of Origio cleavage medium under oil.

In vitro maturation (IVM) of oocytes recovered from ovariectomy specimens in the laboratory: a promising "ex vivo" method of oocyte cryopreservation resulting in the first report of an ongoing pregnancy in Europe.

Purpose: We present our center's experience with 34 consecutive cases who underwent in vitro maturation (IVM) of oocytes obtained from ovariectomy specimens and compare our data with updated literature data.

Methods: Feasibility and efficiency of oocyte collection during ovarian tissue processing was assessed by the recovery rate, maturation rate, and embryological development after IVM.

Results: On average, 14 immature oocytes were retrieved per patient during ovarian tissue processing in 33/34 patients.

Deliveries of normal healthy babies from embryos originating from oocytes showing the presence of smooth endoplasmic reticulum aggregates.

Study Question: Should oocytes showing the presence of smooth endoplasmic reticulum aggregates (SER) be considered for embryo transfer?

Summary Answer: The present study shows that embryos derived from metaphase II oocyte with visible SER (SER+MII) have the capacity to develop normally and may lead to newborns with no major malformations.

What Is Known Already: It has been reported that the presence of SER in the cytoplasm of oocytes has a negative impact on embryo development, and is associated with a decreased clinical outcome and an increased risk of congenital anomalies. Therefore, it has been recommended that embryos derived from SER-positive oocytes should not be transferred.

Human antral follicles <6 mm: a comparison between in vivo maturation and in vitro maturation in non-hCG primed cycles using cumulus cell gene expression.

Within the context of an oocyte in vitro maturation (IVM) program for reproductive treatment, oocyte cumulus complexes (COCs) derived from follicles <6 mm in patients with PCOS were matured in vitro. Key transcripts related to meiotic maturation (FSHR, LHCGR, EGFR, PGR) and oocyte competence (AREG, ADAMTS, HAS2, PTGS2) were quantified in cumulus cells (CCs) before and after maturation. Control CC samples were collected from PCOS and normo-ovulatory patients who had undergone conventional gonadotrophin stimulation for IVF/ICSI.

Establishment of hESC lines from the inner cell mass of blastocyst-stage embryos and single blastomeres of 4-cell stage embryos.

More than 600 human embryonic stem cell (hESC) lines have been reported today at the human European Embryonic Stem Cell Registry ( http://www.hescreg.eu/ ).

Screening ethnically diverse human embryonic stem cells identifies a chromosome 20 minimal amplicon conferring growth advantage.

The International Stem Cell Initiative analyzed 125 human embryonic stem (ES) cell lines and 11 induced pluripotent stem (iPS) cell lines, from 38 laboratories worldwide, for genetic changes occurring during culture. Most lines were analyzed at an early and late passage. Single-nucleotide polymorphism (SNP) analysis revealed that they included representatives of most major ethnic groups.

HLA-G expression in human embryonic stem cells and preimplantation embryos.

Human leukocyte Ag-G, a tolerogenic molecule that acts on cells of both innate and adaptive immunity, plays an important role in tumor progression, transplantation, placentation, as well as the protection of the allogeneic fetus from the maternal immune system. We investigated HLA-G mRNA and protein expression in human embryonic stem cells (hESC) derived from the inner cell mass (ICM) of blastocysts. hESC self-renew indefinitely in culture while maintaining pluripotency, providing an unlimited source of cells for therapy.

Derivation, culture, and characterization of VUB hESC lines.

In this report, we present the derivation and characterization of 15 hESC lines established at the Vrije Universiteit Brussel, Belgium in collaboration with the Universitair Ziekenhuis Brussel, Belgium, using surplus in vitro fertilization embryos and embryos carrying monogenic disorders donated for research. Four lines were derived from blastocyst-stage embryos presumed to be genetically normal, and 11 hESC lines were obtained from embryos shown to carry genetic mutations by preimplantation genetic diagnosis. All the lines express markers of pluripotency as determined by immunocytochemistry and RT-PCR, and formed teratomas when injected into SCID mice.