Goedele Paternot

Intra- and inter-observer analysis in the morphological assessment of early-stage embryos.

BackgroundThe aim of this study was to determine the intra- and inter-observer variability in the evaluation of embryo quality. Multilevel images of embryos on day 1, day 2 and day 3, were analysed using different morphological parameters.MethodsMultilevel images of embryos on day 1, day 2 and day 3, were analysed using a standard scoring system. The kappa coefficient was calculated to measure intra- and inter-observer variability before and after training sessions.ResultsGood to excellent intra-observer agreement was present for most parameters exceptions being scoring the position of pronuclei and the presence of a cytoplasmic halo on day 1, multinucleation on day 2 and the size of fragments on day 3. Inter-observer agreement was only good to excellent for the number of blastomeres on day 2 and day 3 and the orientation of the cleavage axes on day 2. Training sessions had a positive impact on inter-observer agreement.ConclusionIn conclusion, assessment of morphological characteristics of early stage embryos using multilevel images was marked by a high intra-observer and a moderate inter-observer agreement. Training sessions were useful to increase inter-observer agreement.

Intra- and interobserver analysis in the morphological assessment of early stage embryos during an IVF procedure: a multicentre study

BackgroundQuality control programs are necessary to maintain good clinical practice. Embryo grading has been described as one of the external quality assurance schemes. Although the evaluation of embryos is based on the assessment of morphological characteristics, considerable intra- and inter-observer variability has been described. In this multicentre study, the variability in the embryo evaluation has been evaluated using morphological characteristics on day 1, day 2 and day 3 of embryo development.MethodsFive embryologists of four different IVF centers participated in this study. Multilevel images of embryos were presented on a website at different time points to evaluate intra-and inter-observer agreement in the assessment of embryo morphology. The embryos were evaluated on day 1, day 2 and day 3 of their development and each embryologist had to decide if the embryo had to be transferred, cryopreserved or discarded.ResultsBoth intra-observer agreement and inter-observer agreement were good to excellent for the position of the pronuclei on day 1, the number of blastomeres on day 2 and day 3 and the clinical decision (transfer, cryopreservation, discard). For all other characteristics (size of pronuclei, presence of cytoplasomic halo, degree of fragmentation and size of blastomeres) the intra- and inter-observer agreement was moderate to very poor.ConclusionsMono- or multicentre quality control on embryo scoring by morphological assessment can easily be performed through the design of a simple website. In the future the website design can be adapted to generate statistical feedback upon scoring and can even include a training module.

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

BackgroundThe 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.MethodsIn this study, the embryo quality on day 3 was measured as primary outcome. In total, 147 patients younger than 36 years treated with IVF/ICSI during the first or second cycle were included in this study. Embryos were randomly cultured in a sequential (group A) or a single medium (group B) to compare the embryo quality on day 1, day 2 and day 3. The embryo quality was compared in both groups using a Chi-square test with a significance level of 0.05.ResultsAt day 1, the percentage of embryos with a cytoplasmic halo was higher in group B (46%) than in group A (32%). At day 2, number of blastomeres, degree of fragmentation and the percentage of unequally sized blastomeres were higher in group B than in group A. At day 3, a higher percentage of embryos had a higher number of blastomeres and unequally sized blastomeres in group B. The number of good quality embryos (GQE) was comparable in both groups. The embryo utilization rate was higher in group B (56%) compared to group A (49%).ConclusionsAlthough, no significant difference in the number of GQE was found in both media, the utilization rate was significantly higher when the embryos were cultured in the single medium compared to the sequential medium. The results of this study have a possible positive effect on the cumulative cryo-augmented pregnancy rate.Trial registration numberNCT01094314

Computer assisted embryo selection: a benefit in the evaluation of embryo quality?

Embryo selection is based on embryo developmental and morphological characteristics. Standard embryo evaluation has some disadvantages. New technology using multilevel images combined with a computer-assisted scoring system (CASS) has the potential to overcome these disadvantages. The aim of this study was to compare the value of a computer-assisted scoring system (CASS) versus a standard scoring system (SSS) in predicting implantation and live birth. This prospective study included 3185 embryos obtained during 502IVF/intracytoplasmic sperm injection cycles with single-embryo transfer on day 3. Embryos were evaluated with two scoring systems: SSS and CASS. Logistic regression analyses were performed using implantation and live birth as outcomes. According to multiple regression analysis, implantation was influenced by number and size of blastomeres on day 3 using CASS and by all embryo parameters on day 3 using SSS. Combined analysis of both scoring systems revealed that implantation was affected by number and size of blastomeres using CASS and by the degree of embryo fragmentation using SSS. Using live birth as outcome, only the number of blastomeres on day 3, evaluated by SSS and CASS, was predictive. Prediction of implantation and live birth may be superior using CASS when compared with SSS. Embryo selection is currently based on embryo developmental and morphological characteristics of an embryo using a standard scoring system. This evaluation system is limited by a number of disadvantages. New technology using multilevel images combined with a computer-assisted scoring system has the potential to overcome these disadvantages. The aim of this study was to compare the value of such computer-assisted scoring system versus a standard scoring system in predicting implantation and live birth rate. This study included 3185 embryos obtained during 502 IVF or intracytoplasmic sperm injection cycles with single-embryo transfer on day 3. All the embryos were evaluated with two types of scoring systems: a standard scoring system and a computer-assisted scoring system. According to the statistical analysis, the implantation of an embryo was influenced by the number and size of blastomeres on day 3 when evaluated with the computer-assisted scoring system, and by all embryo parameters on day 3 using the standard scoring system. Combined analysis of both scoring systems revealed that implantation was affected by number and size of blastomeres using the computer-assisted scoring system and by the degree of embryo fragmentation using the standard scoring system. Live birth was influenced by the number of blastomeres on day 3 evaluated by both scoring systems. Prediction of embryo implantation and live birth was superior using the computer-assisted scoring system. In conclusion, a computer-assisted scoring system may be superior to a standard scoring system in the prediction of implantation and live birth.

The spatial arrangement of blastomeres at the 4-cell stage and IVF outcome

This study compared the developmental and implantation potential of tetrahedrally arranged versus non-tetrahedrally arranged 4-cell-stage embryos. If the cleavage planes of a 4-cell-stage embryo were perpendicularly orientated, blastomeres were defined as tetrahedrally arranged, while embryos with parallel-orientated cleavage axes were considered as non-tetrahedral embryos. The 4-cell-stage embryos (n=862) examined in this study were obtained from 299 patients aged <36 years. A total of 299 embryos were transferred as a single-embryo transfer on day 3. This study showed that tetrahedral embryos developed into a 8-cell-stage embryo on day 3 more frequently (307, 45% versus 42, 24%; P<0.0001) and also developed more frequently into good-quality embryos (461, 67% versus 67, 38%; P<0.0001) and into excellent-quality embryos (290, 42% versus 34, 19%; P<0.0001). Tetrahedral embryos had a significantly higher implantation potential (98, 38% versus 9, 21%; P=0.038), ongoing pregnancy rate (84, 33% versus 7, 16%; P=0.032) and live birth rate (84, 33% versus 7, 16%; P=0.032). In conclusion, tetrahedral 4-cell-stage embryos on day 2 developed into embryos of better quality on day 3 with a higher implantation potential and live birth rate compared with non-tetrahedral 4-cell-stage embryos. In this study, an additional characteristic of 4-cell-stage embryos has been evaluated. The aim of the study was to evaluate the spatial arrangement of blastomeres in a 4-cell-stage embryo. If the cleavage planes of a 4-cell-stage embryo were perpendicularly orientated (indicating that both axes meet a right angle), blastomeres were defined as tetrahedral arranged while the other embryos were considered as non-tetrahedral embryos. The 4-cell-stage embryos (n=862) examined in this study were obtained from 299 patients aged <36 years. A total of 299 embryos were transferred as a single-embryo transfer on day 3. This study showed that tetrahedral embryos developed into an 8-cell-stage embryo on day 3 more frequently (307, 45% versus 42, 24%; P<0.0001) and also developed more frequently into good-quality embryos (461, 67% versus 67, 38%; P<0.0001) and excellent-quality embryos (290, 42% versus 34, 19%; P<0.0001). Tetrahedral embryos had a significantly higher implantation potential (98, 38% versus 9, 21%; P=0.038), ongoing pregnancy rate (84, 33% versus 7, 16%; P=0.032) and live birth rate (84, 33% versus 7, 16%; P=0.032). In conclusion, tetrahedral 4-cell-stage embryos on day 2 developed into embryos of better quality on day 3 with a higher implantation potential and live birth rate compared with non-tetrahedral 4-cell-stage embryos.

Is there a link between blastomere contact surfaces of day 3 embryos and live birth rate

BackgroundCell-cell communication and adhesion are essential for the compaction process of early stage embryos. The aim of this study was to develop a non-invasive objective calculation system of embryo compaction in order to test the hypothesis that embryos with a larger mean contact surface result in a higher live birth rate compared to embryos with a lower mean contact surface.MethodsMultilevel images of 474 embryos transferred on day 3 were evaluated by the Cellify software. This software calculates the contact surfaces between the blastomeres. The primary outcome of this study was live birth. An ideal range of contact surface was determined and the positive and negative predictive value, the sensitivity, the specificity and the area under the curve for this new characteristic were calculated.ResultsIn total, 115 (24%) transferred embryos resulted in a live birth. Selection of an embryo for transfer on its mean contact surface could predict live birth with a high sensitivity (80%) and high negative predicting value (83%) but with a low positive predictive value (27%), a low specificity (31%) and low area under the ROC curve (0.56). The mean contact surface of embryos cultured in a single medium was significantly higher compared to the mean contact surface of embryos cultured in a sequential medium (p = 0.0003).ConclusionsNeither the mean contact surface nor the number of contact surfaces of a day 3 embryo had an additional value in the prediction of live birth. The type of culture medium, however, had an impact on the contact surface of an embryo. Embryos cultured in a single medium had a significant larger contact surface compared to embryos cultured in the sequential medium.

Triple touch sperm immobilization vs. single touch sperm immobilization in ICSI - a randomised trial.

BackgroundAlthough different techniques for sperm immobilization have been described, their value has not been assessed in an adequately powered randomized study. The aim of this study was to compare two types of sperm immobilization methods prior to ICSI and to test the hypothesis that triple touch immobilization (TTIm) would lead to a higher (5% -65% up to 70%) fertilization rate (FR) than single touch immobilization (STIm).MethodsA total of 3056 metaphase II (MII) oocytes, from 290 patients, were randomly assigned to the STIm group (n = 1528 oocytes; 145 cycles) or to the TTIm group (n = 1528 oocytes; 138 cycles). A total of 1478 oocytes (STIm group) and 1476 oocytes (TTIm group) were used in the statistical analysis. The primary outcome variable was FR. Secondary outcome variables included: number of good quality embryos (GQE) on day 2 and day 3, implantation rate (IR) and implantation with foetal heart beat rate (FHB). Statistical analysis was done using the Fisher Exact test with a significance level of 0.05.ResultsThe results showed no differences in FR between both groups. The proportion of good quality embryos on day 3, was significantly higher in the STIm group (37.5%) compared to the TTIm group (31.8%; p = 0.02).ConclusionsIn this RCT, the hypothesis that the post-ICSI FR would be higher after TTIm than after STIm was not confirmed and the number of good quality embryos on day 3 was significantly lower in the TTIm group than in the STIm group. These data suggest that more ‘aggressive’ TTIm technique has no advantages compared to the STIm technique.