Preimplantation genetic diagnosis of alpha-thalassemia-SEA using novel multiplex fluorescent PCR

Purpose  

Preimplantation genetic diagnosis (PGD) is an alternative to prenatal diagnosis (PND) giving couples at risk a chance to start a pregnancy with a disease-free baby. This study aimed to develop a new PGD protocol for alpha-thalassemia^-SEA mutation, the commonest Mendelian disorder.     

Preimplantation Genetic Diagnosis—An Integral Part of Assisted Reproduction

Conference Report

Preimplantation Genetic Diagnosis—An Integral Part of Assisted Reproduction     

Preimplantation genetic diagnosis for chromosome rearrangements – one blastomere biopsy versus two blastomere biopsy

Purpose

Preimplantation Genetic Diagnosis (PGD) has proven to be a useful reproductive option for carriers of some chromosome rearrangements. The data presented in this study compares the impact of one versus two blastomere biopsy on the likelihood of achieving a PGD result, as well as the effect on subsequent embryo development and clinical outcomes.

Methods

IVF-PGD couples had either one or two blastomeres biopsied from all embryos with ≥7 blastomeres on day 3 post oocyte collection. These blastomeres were assessed for the specific chromosome rearrangement using Fluorescent In-situ Hybridisation (FISH). Further embryo development was monitored on days 4 and 5. Clinical outcomes were assessed retrospectively.

Results

The data shows that statistically more embryos achieved a PGD result following two blastomere biopsy, compared with one blastomere biopsy (92 % versus 88 %, respectively). Furthermore it was found that embryo development and clinical outcomes were similar between the two biopsy groups.

Conclusions

Based on this analysis it appears that the biopsy of two blastomeres from embryos with ≥7 blastomeres on day 3 is a valid and successful approach for couples presenting for IVF-PGD for a chromosome rearrangement.     

Biomarkers of human oocyte developmental competence expressed in cumulus cells before ICSI: a preliminary study

Purpose  

To identify reliable genomic biomarkers expressed in cumulus cells that accurately and non-invasively predict the oocyte developmental competence and reinforce the already used morphological criteria.     

Genetic Screening and Early Recurrent Pregnancy Loss

Purpose of Review

The purpose of this review is to identify current data and provide a clear treatment path specifically the role of preimplantation genetic screening (PGS) for the evaluation and treatment of recurrent early pregnancy loss (RPL).

Recent Findings

Recent data within the causes of RPL have established that the role of genetics, specifically chromosomal aneuploidy, is far more significant as a cause of the disorder than has been traditionally believed. Current data suggests that at least 50% of all first trimester losses are a result of such chromosomal copy number errors. Furthermore, therapeutic techniques, such as Preimplantation Genetic Screening (PGS) are now available to reduce the chances of aneuploidy in appropriately selected couples with RPL.

Summary

Recurrent early pregnancy loss (RPL) represents a significant challenge for many couples wishing to grow their family. The clinical management of RPL is challenging given the multiple causes of pregnancy loss. The past several decades have seen tremendous advances in the understanding of and treatment for this heterogeneous disorder. Thankfully, a definite cause of pregnancy loss can be established in over half of couples after a thorough evaluation. The evaluation of RPL may be conducted in a structured manner, focusing on a defined set of etiological categories including anatomic, genetic, immunologic, endocrinologic, infectious, and environmental.

     

A study of the effect of an extremely low oxygen concentration on the development of human embryos in assisted reproductive technology

Purpose  

To determine whether embryos cultured with a low oxygen level (2%) brought about beneficial effects on the outcome of ART.     

Reducing inter-observer variability in embryo evaluation by means of training courses

Purpose  

To study the utility of a training session offered to junior embryologists, comparing the results obtained with those reported by a group of senior embryologists.     

Confirmation rates of array-CGH in day-3 embryo and blastocyst biopsies for preimplantation genetic screening

Purpose

The purpose of this study was to compare the confirmation rate of day-3 embryo biopsy (blastomere) and trophectoderm biopsy using array-comparative genomic hybridization (array-CGH) technology.

Methods

A blinded study was conducted to re-analyse 109 embryos previously diagnosed as chromosomally abnormal by array-CGH. Preimplantation genetic screening (PGS) was performed using array-CGH on day 3 (n = 50) or day 5 (n = 59). Partial chromosome gains or losses were excluded (n=6), and only whole chromosome aneuploidies were considered. Re-analysis of whole blastocysts was carried out following the same array-CGH protocol used for PGS.

Results

The PGS result was confirmed in the whole blastocyst in (a) 49/50 (98 %) abnormal embryos after day-3 biopsy and (b) 57/59 (96.6 %) abnormal embryos after trophectoderm biopsy. One embryo (1/50; 2 %) was diagnosed as abnormal, with monosomy 18, on day 3, and software analysis of the whole blastocyst gave a euploid result; however, a mosaic pattern was observed for monosomy 18 in the whole blastocyst. Two trophectoderm biopsy cases (3.4 %) did not have the abnormalities (trisomy 7, and trisomy 1 and 4, respectively) verified in the whole embryo. Concordance rates for both biopsy strategies and for individual chromosomes were evaluated by Fisher’s exact test and showed no significant differences.

Conclusions

Both types of biopsies showed similar high concordance rates with whole blastocyst results. Therefore, regarding the confirmation rates shown in this work, day-3 embryo biopsies can be representative of the whole embryo and both types of biopsy can be used for clinical analysis in PGS following the described array-CGH protocol.     

The effects of different laser pulse lengths on the embryo biopsy procedure and embryo development to the blastocyst stage

Purpose  

A laser is commonly used to remove a blastomere from an embryo for genetic testing. The laser uses intense heat which could possibly disrupt embryo development. It is the goal of this study to test the effects of different laser pulse lengths (and consequently heat) on the embryo biopsy procedure and embryo development.     

Effects of embryo transfer quality on pregnancy and live birth delivery rates

Background  

To analyze the effects of embryo transfer (ET) quality on clinical pregnancy (CPR) and live birth delivery rates (LBDR).     

Possible selection of viable human blastocysts after vitrification by monitoring morphological changes

Purpose

Morphological assessment of human blastocysts has been effective for selecting embryos with high potential. However, they often show repeated shrinkage and expansion toward their hatching. Here we assessed whether capturing morphological changes over time of vitrified–warmed blastocysts could lead to a better selection of viable embryos from shrunken blastocysts.

Methods

The implantation rates of vitrified–warmed blastocysts that were shrunken or expanded (developing) at the time of loading for transfer were compared among 2,729 cycles that were subjected to single blastocyst transfer. Vitrified (107) and fresh blastocysts (17) were donated for the experimental study. To assess the relationship between morphology (expanded vs. shrunken) and the mitochondrial respiration of blastocysts, the oxygen consumption rate (OCR) was analyzed for 55 specimens using an uncoupler of oxidative phosphorylation. The remaining 69 blastocysts were used for recording morphological changes every 15 min for 48 h after warming.

Results

Because there were no surplus embryos, 7 % of the vitrified–warmed blastocysts were shrunken and transferred. The shrunken embryos had sufficient implantation ability (40 %). The OCR of the shrunken embryos was significantly lower than that of their expanded counterparts. Upon exposure to the uncoupler, the OCR of some shrunken embryos increased to levels similar to the expanded specimens. Time-lapse images revealed some shrunken embryos which formed blastocoel by 5 h following warming exhibited developmental competence to the hatched stage.

Conclusions

Data of the present study suggest a group of shrunken blastocysts contains many viable and clinically available embryos and time-lapse observation of vitrified–warmed blastocysts is a potential method to distinguish viable embryos from shrunken blastocysts.     

The utility of embryo banking in order to increase the number of embryos available for preimplantation genetic screening in advanced maternal age patients

Purpose  

To determine if embryo banking with PGS is more optimal than proceeding with PGS regardless of embryo number.     

The influence of early cleavage on embryo developmental potential and IVF/ICSI outcome

Purpose  

To observe whether early cleavage can be a predictor of embryo developmental potential, pregnancy and implantation rates.     

Establishment of mouse embryonic stem cells from isolated blastomeres and whole embryos using three derivation methods

Purpose  

The aim of the present study is to compare three previously described mouse embryonic stem cell derivation methods to evaluate the influence of culture conditions, number of isolated blastomeres and embryonic stage in the derivation process.     

Use of the natural cycle and vitrification thawed blastocyst transfer results in better in-vitro fertilization outcomes

Purpose  

To compare the IVF outcomes of vitrification-thawed blastocyst transfer cycles utilizing different endometrial preparation methods.     

Dipeptide forms of glycine support mouse preimplantation embryo development in vitro and provide protection against high media osmolality

Purpose  

To examine potential benefits of dipeptide forms of amino acids for embryo culture by determining ability of dipeptide glycine forms to support embryo development, act as osmolytes, and reduce ammonia production.     

Relationship between meiotic spindle characteristics in human oocytes and the timing of the first zygotic cleavage after intracytoplasmic sperm injection

Purpose  

To investigate the relationship between meiotic spindle characteristics in human oocytes and the timing of the first zygotic cleavage after intracytoplasmic sperm injection (ICSI).     

Effect of <Emphasis Type="Italic">Papaver rhoeas</Emphasis> extract on in vitro maturation and developmental competence of immature mouse oocytes

Purpose  

This experiment examined the effect of Papaver rhoeas L. extract on in vitro maturation, in vitro fertilization (IVF) and subsequent developmental competence of mouse oocytes.     

Correlation between embryological factors and pregnancy rate: development of an embryo score in a cryopreservation programme

Purpose  

To establish which embryo parameters, in frozen thawed embryo transfers, have the highest prognosis value in the establishment of pregnancy. The relative importance of different embryo parameters is used to develop an embryo score.     

Gonadal and nongonadal FSHR and LHR dysfunction during lipopolysaccharide induced failure of blastocyst implantation in mouse

Purpose  

The purpose of the present study was to investigate the impact of lipopolysaccharide (LPS) on follicle-stimulating hormone (FSH), luteinizing hormone (LH) and their receptors during preimplantation days of pregnancy.