Assessment of endometrial and ovarian characteristics using three dimensional power Doppler ultrasound to predict response in frozen embryo transfer cycles

Objective  

To evaluate whether endometrial or ovarian parameters as measured using 3D power Doppler ultrasound would predict the outcome in frozen embryo transfer (FET) cycles.     

Evaluation of day one embryo quality and IVF outcome – a comparison of two scoring systems

Background  

The aim of our retrospective study was to compare the clinical usefulness of two non-invasive embryo scoring systems based either on a simplified pronuclear morphology of the zygote or on early cleavage rate, as well as their combination, for the selection of embryos with the best implantation potential in embryo transfer (ET).     

Combined analysis of endometrial thickness and pattern in predicting outcome of in vitro fertilization and embryo transfer: a retrospective cohort study

Objective  

To evaluate the combined effect of endometrial thickness and pattern on clinical outcome in patients undergoing in vitro fertilization/intracytoplasmic sperm injection and embryo transfer (IVF/ICSI-ET).     

The correlation between endometrial thickness and outcome of in vitro fertilization and embryo transfer (IVF-ET) outcome

Background  

To evaluate the relationship between endometrial thickness on day of human chorionic gonadotrophin administration (hCG) and pregnancy outcome in a large number of consecutive in vitro fertilization and embryo transfer (IVF-ET) cycles.     

Endometrial thickness, Caucasian ethnicity, and age predict clinical pregnancy following fresh blastocyst embryo transfer: a retrospective cohort

Background  

In-vitro fertilization (IVF) with blastocyst as opposed to cleavage stage embryos has been advocated to improve success rates. Limited information exists on which to predict which patients undergoing blastocyst embryo transfer (BET) will achieve pregnancy. This study's objective was to evaluate the predictive value of patient and cycle characteristics for clinical pregnancy following fresh BET.     

Severe teratozoospermia and its influence on pronuclear morphology,embryonic cleavage and compaction

Background  

Fertilization, cell division and embryo development depend on genomic contributions from male and female gametes. We hypothesize that teratozoospermic sperm influences early embryo development and embryo compaction.     

Analysis of cat oocyte activation methods for the generation of feline disease models by nuclear transfer

Background  

Somatic cell nuclear transfer in cats offers a useful tool for the generation of valuable research models. However, low birth rates after nuclear transfer hamper exploitation of the full potential of the technology. Poor embryo development after activation of the reconstructed oocytes seems to be responsible, at least in part, for the low efficiency. The objective of this study was to characterize the response of cat oocytes to various stimuli in order to fine-tune existing and possibly develop new activation methods for the generation of cat disease models by somatic cell nuclear transfer.     

Comparative maturation of cynomolgus monkey oocytes in vivo and in vitro

Background  

In vitro maturation (IVM) of oocytes followed by fertilization in vitro (IVF) and embryo transfer offers an alternative to conventional IVF treatment that minimises drug administration and avoids ovarian hyperstimulation. However, the technique is less efficient than maturation in vivo. In the present study, a non-human primate model was used to address the hypothesis that the number of oocytes is increased and their nuclear and cytoplasmic maturity after IVM are improved when maturation is initiated in vivo by priming with hCG.     

Impact of proximal cytoplasmic droplets on quality traits and in-vitro embryo production efficiency of cryopreserved bull spermatozoa

Background  

Proximal cytoplasmic droplets (PCDs), a remnant of germ cell cytoplasm, are common non-specific morphological defects in bovine semen. This study evaluated the effect of higher percentages of PCDs on the quality of frozen-thawed bovine semen, embryo production and early embryo development.     

<Emphasis Type="Italic">In vitro</Emphasis>effects of relaxin on gene expression in porcine cumulus-oocyte complexes and developing embryos

Background  

Relaxin hormone peptide is found in porcine follicular and utero-tubal fluids, but its possible actions during early embryo development are still undetermined. Here, we investigated the effects of porcine relaxin during oocyte maturation and embryo development, and gene expression in the pig.     

Impact of GnRH analogues on oocyte/embryo quality and embryo development in in vitro fertilization/intracytoplasmic sperm injection cycles: a case control study

Background  

Despite the clinical outcomes of ovarian stimulation with either GnRH-agonist or GnRH-antagonist analogues for in vitro fertilization (IVF) being well analysed, the effect of analogues on oocyte/embryo quality and embryo development is still not known in detail. The aim of this case-control study was to compare the efficacy of a multiple-dose GnRH antagonist protocol with that of the GnRH agonist long protocol with a view to oocyte and embryo quality, embryo development and IVF treatment outcome.     

Role of chromosome stability and telomere length in the production of viable cell lines for somatic cell nuclear transfer

Background  

Somatic cell nuclear transfer (SCNT) provides an appealing alternative for the preservation of genetic material in non-domestic and endangered species. An important prerequisite for successful SCNT is the availability of good quality donor cells, as normal embryo development is dependent upon proper reprogramming of the donor genome so that embryonic genes can be appropriately expressed. The characteristics of donor cell lines and their ability to produce embryos by SCNT were evaluated by testing the effects of tissue sample collection (DART biopsy, PUNCH biopsy, post-mortem EAR sample) and culture initiation (explant, collagenase digestion) techniques.     

Analysis of pronuclear zygote configurations in 459 clinical pregnancies obtained with assisted reproductive technique procedures

Background  

Embryos selection is crucial to maintain high performance in terms of pregnancy rate, reducing the risk of multiple pregnancy during IVF. Pronuclear and nucleolar characteristics have been proposed as an indicator of embryo development and chromosomal complement in humans, providing information about embryo viability.     

Effect of transporting donor or recipient does and their embryos on the outcome of fresh embryo transfer in Boer goats

Between-farm embryo transfer of livestock animals can potentially increase the spread of quality genetic material. However, the transporting of donor or recipient animals or their embryos has become a practical problem. The objective of this study was to compare the effect of transporting donor and recipient does and their embryos between various farms on inter-farm fresh embryo transfer in Boer goats. Results indicate the transportation of donor does within 4 h before embryo collection not to have a significant effect on embryo recovery number, embryo survival rate and the subsequent pregnancy in recipient does. Also, the transportation of embryos at 36.5–38 °C within 2 h before embryo transfer did not significantly affect the embryo survival rate and subsequent pregnancy rate, but the transportation of embryos at 20 °C resulted in a significant (P < 0.05) lower survival rate (41.7%) and pregnancy rate (42.0%). The transportation of recipient does resulted in a significantly lower pregnancy rate (42.0%) and embryo survival rate (32.1%) than the transportation of donor does and embryos. Results suggest the transportation of donor does to be the best method for embryo transfer programs on the farm. Alternatively, the supply of fresh embryos kept at body temperature (36.5 °C) was also preferred for short or long distances between farms.     

Identification and expression analysis of genes associated with bovine blastocyst formation

Background  

Normal preimplantation embryo development encompasses a series of events including first cleavage division, activation of the embryonic genome, compaction and blastocyst formation.     

Effect of adiponectin on bovine granulosa cell steroidogenesis,oocyte maturation and embryo development

Background  

Adiponectin is an adipokine, mainly produced by adipose tissue. It regulates several reproductive processes. The protein expression of the adiponectin system (adiponectin, its receptors, AdipoR1 and AdipoR2 and the APPL1 adaptor) in bovine ovary and its role on ovarian cells and embryo, remain however to be determined.     

Novel gene expression patterns along the proximo-distal axis of the mouse embryo before gastrulation

Background  

To date, the earliest stage at which the orientation of the anterior-posterior axis in the mouse embryo is distinguishable by asymmetric gene expression is shortly after E5.5. At E5.5, prospective anterior markers are expressed at the distal tip of the embryo, whereas prospective posterior markers are expressed more proximally, close to the boundary with the extraembryonic region.     

<Emphasis Type="Italic">Arabidopsis thaliana</Emphasis> outer ovule integument morphogenesis: Ectopic expression of <Emphasis Type="Italic">KNAT1</Emphasis>reveals a compensation mechanism

Background  

The Arabidopsis outer ovule integument is a simple two-cell layered structure that grows around the developing embryo and develops into the outer layer of the seed coat. As one of the functions of the seed coat is the protection of the plant embryo, the outer ovule integument is an example for a plant organ whose morphogenesis has to be precisely regulated.     

Early embryo development in a sequential versus single medium: a randomized study

Background  

The success of in vitro fertilization techniques is defined by multiple factors including embryo culture conditions, related to the composition of the culture medium. In view of the lack of solid scientific data and in view of the current general belief that sequential media are superior to single media, the aim of this randomized study was to compare the embryo quality in two types of culture media.