Influence of the shortened warming protocol on human blastocyst viability: an in-vitro experimental study.

Research Question: Does the shortened warming protocol impact the cell viability and outgrowth competence of human vitrified blastocysts warmed with or without fatty acids?

Design: In this study, 326 discarded vitrified human blastocysts donated for research by consenting couples were used. The blastocysts were randomly allocated to five groups depending on the warming solutions, protocols and recovery culture media: the control-conventional, control-shortened, FA-conventional, FA-shortened, and FA-shortened/recovery culture with fatty acid (FA-shortened/RF) groups. The blastocysts were warmed with or without fatty acids following the manufacturer's instruction (conventional method) or using the shortened method, in which blastocysts were immersed in a thawing solution for 1 min and then cultured in the recovery medium for 2 h.

Developmental perturbation in human embryos: Clinical and biological significance learned from time-lapse images.

Background: Time-lapse technology (TLT) has gained widespread adoption worldwide. In addition to facilitating the undisturbed culture of embryos, TLT offers the unique capability of continuously monitoring embryos to detect spatiotemporal changes. Although these observed phenomena play a role in optimal embryo selection/deselection, the clinical advantages of introducing TLT remain unclear.

Fatty acid supplementation during warming improves pregnancy outcomes after frozen blastocyst transfers: a propensity score-matched study.

This study aimed to examine the viability of human blastocysts after warming with fatty acids (FAs) using an in vitro outgrowth model and to assess pregnancy outcomes after a single vitrified-warmed blastocyst transfer (SVBT). For the experimental study, we used 446 discarded vitrified human blastocysts donated for research purposes by consenting couples. The blastocysts were warmed using FA-supplemented (FA group) or non-FA-supplemented (control group) solutions.

Fatty acid supplementation into warming solutions improves pregnancy outcomes after single vitrified-warmed cleavage stage embryo transfers.

Purpose: This study aimed to examine the embryonic development of human 4-cell stage embryos after warming with fatty acids (FAs) and to assess the pregnancy outcomes after single vitrified-warmed cleavage stage embryo transfers (SVCTs).

Methods: Experimental study: A total of 217 discarded, vitrified human 4-cell stage embryos donated for research by consenting couples were used. The embryos were warmed using the fatty acid (FA)-supplemented solutions (FA group) or nonsupplemented solutions (control group).

Post-warming culture of human vitrified blastocysts with prolactin improves trophoblast outgrowth.

Background: Human embryos express the prolactin (PRL) receptor at the morula and blastocyst stages. Treatment with PRL from cleavage to the blastocyst stage improves blastocyst outgrowth on fibronectin-coated dishes. However, whether post-warming PRL treatment of blastocysts cultured without PRL could improve outgrowth competence remains unknown.

Preimplantation Genetic Testing for Aneuploidy for Recurrent Pregnancy Loss and Recurrent Implantation Failure in Minimal Ovarian Stimulation Cycle for Women Aged 35-42 Years: Live Birth Rate, Developmental Follow-up of Children, and Embryo Ranking.

This study was aimed at exploring the benefits of preimplantation genetic testing for aneuploidy (PGT-A) in ensuring a successful pregnancy in patients with recurrent pregnancy loss (RPL) caused by an abnormal number of chromosomes in the embryo and recurrent implantation failure (RIF). Thirty-two patients who underwent PGT-A (18 in the RIF protocol and 14 in the RPL protocol) were enrolled in the study, and 2556 patients who did not undergo PGT-A during the same in vitro fertilization (IVF) treatment period were enrolled as controls. All patients underwent minimal stimulation cycle IVF.

Time from trophectoderm biopsy to vitrification affects the developmental competence of biopsied blastocysts.

Purpose: The present study aimed to examine the correlations of the time interval from trophectoderm (TE) biopsy to vitrification with the blastocyst survival rate and blastocyst outgrowth ability.

Methods: A total of 1,202 mouse blastocysts were randomly divided into control (non-biopsy) and TE biopsy groups. The biopsied blastocysts were vitrified at various time points.

Characteristics of the cytoplasmic halo during fertilisation correlate with the live birth rate after fresh cleaved embryo transfer on day 2 in minimal ovarian stimulation cycles: a retrospective observational study.

Background: Information regarding the influence of cytoplasmic events during fertilisation on the clinical outcome remains limited. The cytoplasmic halo is one of these events. A previous study that used time-lapse technology found an association of the presence and morphokinetics of the cytoplasmic halo with cleavage patterns, development to the blastocyst stage, and the ongoing pregnancy rate after blastocyst transfer.

Spatiotemporal perturbations of pronuclear breakdown preceding syngamy affect early human embryo development: a retrospective observational study.

Purpose: During fertilisation, female and male pronuclei (PNs) migrate to the centre of the ooplasm, juxtapose, and break down synchronously in preparation for the first mitosis. While PN non-juxtaposition and PN breakdown (PNBD) asynchrony are occasionally observed, their developmental implications remain uncertain. This study investigated the possible relationships among the two phenomena, preimplantation development patterns, and live birth rates in single blastocyst transfers.

Effects of fatty acid supplementation during vitrification and warming on the developmental competence of mouse, bovine and human oocytes and embryos.

Research Question: Does fatty acid supplementation in vitrification and warming media influence developmental competence in oocytes after vitrification and warming?

Design: Mouse oocytes and four-cell embryos were vitrified and warmed with solutions supplemented with fatty acid and cultured to the blastocyst stage. To study lipid metabolism after vitrification, quantitative real-time polymerase chain reaction was used to analyse the expression of genes related to beta oxidation in mouse embryos vitrified and warmed with or without fatty acids. The effects of fatty acid supplementation in the warming solutions on the developmental competence of bovine and human embryos were analysed.

Prolactin receptor expression and its role in trophoblast outgrowth in human embryos.

Research Question: What is the gene expression pattern of prolactin receptor (PRLR) in human pre-implantation embryos and what are its functions during the embryonic development and adhesion process?

Design: A total of 405 discarded human vitrified oocytes and embryos donated for research by consenting couples were used in this study. The oocytes and embryos were used to analyse PRLR expression and to evaluate the influence of prolactin (PRL) supplementation in the embryo culture medium on embryo developmental competence and viability. The rates of blastocyst development and adhesion, outgrowth area, cytoskeletal reorganization and nascent adhesion formation were compared between groups.

Cytoplasmic halo characteristics during fertilization and their implications for human preimplantation embryo development and pregnancy outcome.

Research Question: Is the spatiotemporal phenomenology of the cytoplasmic halo during fertilization related to embryonic competence?

Design: Time-lapse images from 1009 zygotes were retrospectively analysed from 560 patients who underwent IVF with minimal stimulation and single vitrified-warmed blastocyst transfer between April 2017 and March 2018. Halo presence and morphokinetics were monitored and compared relative to embryo quality, blastocyst expansion and ongoing pregnancy.

Results: Halo was observed in 88% of fertilized oocytes.

Blastomere movement post first cell division correlates with embryonic compaction and subsequent blastocyst formation.

Background: Blastomere movement (BMov) occurs after the first cell division in human embryos. This movement has been suggested as a prognostic parameter for pregnancy outcome prediction following cleavage-stage embryo transfer. However, the effect of BMov on preimplantation development and pregnancy outcome after blastocyst transfer remains unclear.

Prolonged blastomere movement induced by the delay of pronuclear fading and first cell division adversely affects pregnancy outcomes after fresh embryo transfer on Day 2: a time-lapse study.

Research Question: What is the incidence, origin and clinical significance of blastomere movement after the first cell division in the human embryo?

Design: A total of 1096 embryos, cultured in the EmbryoScope+ ® time-lapse system and subjected to a single fresh cleaved embryo transfer, were retrospectively analysed. Type and duration of blastomere movement (dBMov) between the first (t2) and second cell division (t3) was monitored, and the ratio of dBMov during the 2-cell stage [dBMov/(t3-t2)] was calculated. Morphological evaluation of embryos was performed by referring to the size of the blastomere and fragmentation after first division in addition to Veeck's criteria on Day 2.

Developmental Competence of Vitrified-Warmed Bovine Oocytes at the Germinal-Vesicle Stage is Improved by Cyclic Adenosine Monophosphate Modulators during In Vitro Maturation.

Cryopreservation of mature oocytes and embryos has provided numerous benefits in reproductive medicine. Although successful cryopreservation of germinal-vesicle stage (GV) oocytes holds promise for further advances in reproductive biology and clinical embryology fields, reports regarding cryopreservation of immature oocytes are limited. Oocyte survival and maturation rates have improved since vitrification is being performed at the GV stage, but the subsequent developmental competence of GV oocytes is still low.

Broadband regenerative wavelength conversion and multicasting using triple-stage semiconductor-based wavelength converters.

We demonstrate broadband wavelength conversion with a 320 nm operating wavelength range and channel spacing flexible wavelength-division-multiplexing (WDM) multicasting from a 1550 nm signal using a triple-stage cascaded semiconductor-optical-amplifier-based wavelength converter.

Performances of a widely pulsewidth-tunable multiwavelength pulse generator by a single SOA-based delayed interferometric switch.

Performances of a multiwavelength optical pulse generator by utilizing a single semiconductor optical amplifier (SOA)-based delayed interferometric switch are investigated. The generator enables us to generate multiwavelength clock pulse trains, which are synchronized with an optical clock. Moreover, the output waveform can be easily controlled by adjusting the time delay and phase offset of the interferometric switch.

Performance improvement of optical RZ-receiver by utilizing an all-optical waveform converter.

A practical receiver scheme with all-optical waveform conversion is proposed and demonstrated. To mitigate influence of the timing jitter of the received signal, the proposed receiver employs a semiconductor optical amplifier (SOA)-based waveform converter, which can generate signal pulses with a rectangular-like profile. We have evaluated the receiver performances of the conventional and proposed schemes.