Fabrice Guerif

Single Day 2 embryo versus blastocyst-stage transfer: a prospective study integrating fresh and frozen embryo transfers

BACKGROUND Whether extended culture allowing selection of embryos with high development potential has any advantage over cleavage-stage embryo transfer remains a matter of debate. Among the currently unsolved questions, the cumulative delivery rate resulting from fresh and frozen embryo transfers needs to be taken into account in both strategies. The aim of our study was, therefore, to compare the efficacy of single embryo transfer either on Day 2 or on Day 5/6 combining fresh and frozen embryo transfers. METHODS A prospective study including 478 couples assigned on a voluntary basis to undergo elective single embryo transfer (eSET, n = 243) on Day 2 or single blastocyst transfer (SBT, n = 235) on Day 5/6 was performed. The primary outcome measurement was the cumulative delivery rate including fresh and frozen-thawed cycles in both groups. RESULTS The delivery rate per cycle following fresh embryo transfer was significantly higher in the SBT group compared with the eSET group (P < 0.01). Conversely, frozen embryo and/or blastocyst transfers tended to result in a higher number of deliveries in the eSET compared with the SBT group. Altogether, the cumulative delivery rate per couple, including fresh and frozen embryo transfers, was similar between the two groups (37.9% versus 34.2% in the SBT and eSET groups, respectively). CONCLUSIONS The observed cumulative delivery rates in this study do not allow us to take a position in favor of SBT or eSET. An improvement in blastocyst cryopreservation may change this attitude.

Genomic assessment of human cumulus cell marker genes as predictors of oocyte developmental competence: impact of various experimental factors.

Background Single embryo transfer (SET) is the most successful way to reduce the frequency of multiple pregnancies following in vitro fertilisation. However, selecting the embryo for SET with the highest chances of pregnancy remains a difficult challenge since morphological and kinetics criteria provide poor prediction of both developmental and implantation ability. Partly through the expression of specific genes, the oocyte-cumulus interaction helps the oocyte to acquire its developmental competence. Our aim was therefore to identify at the level of cumulus cells (CCs) genes related to oocyte developmental competence. Methodology/Principal Findings 197 individual CCs were collected from 106 patients undergoing an intra-cytoplasmic sperm injection procedure. Gene expression of CCs was studied using microarray according to the nuclear maturity of the oocyte (immature vs. mature oocyte) and to the developmental competence of the oocyte (ability to reach the blastocyst stage after fertilisation). Microarray study was followed by a meta-analysis of the behaviour of these genes in other datasets available in Gene Expression Omnibus which showed the consistency of this list of genes. Finally, 8 genes were selected according to oocyte developmental competence from the 308 differentially expressed genes (p<0.0001) for further validation by quantitative PCR (qPCR). Three of these 8 selected genes were validated as potential biomarkers (PLIN2, RGS2 and ANG). Experimental factors such as inter-patient and qPCR series variability were then assessed using the Generalised Linear Mixed Model procedure, and only the expression level of RGS2 was confirmed to be related to oocyte developmental competence. The link between biomarkers and pregnancy was finally evaluated and level of RGS2 expression was also correlated with clinical pregnancy. Conclusion/Significance RGS2, known as a regulator of G protein signalling, was the only gene among our 8 selected candidates biomarkers of oocyte competence to cover many factors of variability, including inter-patient factors and experimental conditions.

Efficacy of blastocyst transfer after implantation failure

Clinicians who treat unsuccessful couples despite repeated transfers of good quality embryos face a challenge. Among the various strategies that have been described, embryo transfer at the blastocyst stage has been postulated to improve implantation. A prospective non-randomized analysis was performed in 276 IVF patients who failed to conceive after at least two early embryo transfers of at least two grade 1-2 embryos per cycle. For the next attempt, couples chose between day 2 embryo transfer (D2 group; n = 147) and day 5/6 blastocyst transfer (D5/D6 group; n = 129) before starting the following attempt. Embryo quality was assessed and results were expressed as clinical pregnancy, live birth and implantation rates per cycle. Embryo grade 1 number was similar between both groups, whereas mean embryo score of the whole cohort was slightly higher in the D2 group. The live birth rates per cycle (27.9 versus 19.7%) and implantation rates per cycle (25.4 versus 12.4%) were higher in the D5/D6 group compared with the D2 group. Improved embryo selection and uterine receptivity may explain the additional benefit of embryo transfer at the blastocyst stage for couples with repeated implantation failures.

Does early morphology provide additional selection power to blastocyst selection for transfer

Routine early developmental parameters are widely used in IVF centres to evaluate embryo development and fresh single-blastocyst transfer currently seems superior to single-embryo transfer. Would early morphological parameters help to choose the single blastocyst to be transferred, thereby improving the chances of implantation and live birth rate? This prospective observational study analysed the individual outcomes of 2617 embryos from 511 IVF couples scheduled for a single-blastocyst transfer. Embryo and blastocyst scores were constructed. There was a clear relationship between the kinetics and morphology of blastocysts and further implantation and live birth rate. There was a limited predictive value of embryo score with regard to blastocyst development and growth kinetics. Implanted and non-implanted blastocysts showed similar embryo scores. Thus usual morphological parameters on days 1 and 2 seem to have no additional value in indicating the right blastocyst to transfer. Non-invasive approaches might be helpful to increase the chances of implantation in the future.

Serum antimüllerian hormone is not predictive of oocyte quality in vitro fertilization.

OBJECTIVES The assessment of the ovarian reserve is mandatory in women undergoing assisted reproduction. Antimüllerian hormone (AMH) produced by granulosa cells from preantral and early antral follicles, is a promising indicator of ovarian reserve. However, few studies have evaluated the predictive value of AMH on oocyte quality. MATERIAL AND METHODS A retrospective study was undertaken at the Bretonneau University Hospital of Tours. A total of 559 women undergoing in vitro fertilization treatment between January 2007 and December 2007 were included in the study. Serum AMH levels were determined by using an ultrasensitive ELISA test. Total number of oocytes, rate of mature oocytes, fertilization rate, embryo quality and clinical pregnancy rate were recorded. RESULTS Serum AMH was significantly lower in groups of patients with few oocytes collected. However, serum AMH was not predictive of nuclear maturity of oocytes, fertilization rate and quality of early embryos. Additionally, low levels of AMH do not preclude clinical pregnancy, in in vitro fertilization. CONCLUSION At the moment, serum AMH is a relatively predictive indicator of the ovarian reserve, in terms of quantity but not in terms of quality. Moreover, it is still not possible to determine serum AMH cut-off value to predict clinical pregnancy in IVF programmes.

Semen variation in a population of fertile donors: evaluation in a French centre over a 34-year period

Although it has been suspected that there is a decrease in semen quality over time, the results reported to date remain debatable because of methodological issues. The aim of the study reported here was to investigate the evolution of semen quality over time in a population of 1114 fertile candidates for sperm donation at CECOS, Tours, between 1976 and 2009. We investigated semen volume, sperm concentration, progressive motility, vitality, percentage of normal forms and multiple abnormalities index of the first ejaculate in this population. We did not find a decline in semen volume, whereas we observed a significant decrease in total sperm count (from 443.2 million in 1976 to 300.2 million in 2009), motility (from 64% in 1976 to 49% in 2009) and vitality (from 88% to 80%). Moreover, a significant decline in the percentage of normal forms was noted between 1976 and 1997 (from 67% to 26%) with a steady rise in the multiple abnormalities index between 1998 and 2009 (from 1.19 to 1.65). This study involving a population of fertile men from a restricted area revealed various degrees of decline in semen parameters over a period of 34 years. These findings will have to be compared with findings in other geographical areas.

A simple approach for COnsumption and RElease (CORE) analysis of metabolic activity in single mammalian embryos.

Non-invasive assay of the consumption and release of metabolites by individual human embryos could allow selection at the cleavage stage of development and facilitate Single Embryo Transfer in clinical IVF but will require simple, high throughput, sensitive methods applicable to small volume samples. A rapid, simple, non-invasive method has therefore been devised using a standard fluorescence plate reader, and used to measure the consumption of pyruvate and glucose, and release of lactate by single bovine embryos at all stages of preimplantation development in culture; amino acid profiles have been determined using HPLC. Early embryos with an ‘intermediate’ level (6.14±0.27 pmol/embryo/h) of pyruvate uptake were associated with the highest rate (68.3%) of blastocyst development indicating that a mid “optimum” range of pyruvate consumption correlates with high viability in this bovine model.

Overnight incubation improves selection of frozen–thawed blastocysts for transfer: preliminary study using supernumerary embryos

A study was undertaken to determine whether the interval between thawing and transfer influences both biological and clinical outcomes of cryopreserved blastocysts, using supernumerary embryos cultured in sequential media. One hundred and seventy-two patients who underwent blastocyst thawing without any exclusion criteria were included in this single center prospective study of blastocyst thawing cycles. Outcome of 338 blastocysts originating from culture of supernumerary embryos in sequential media was analyzed after 4 or 20 h of culture between thawing and transfer. Survival rate, re-expansion and hatching rates for surviving blastocysts, implantation rates (IRs), pregnancy and miscarriage rates were studied. Blastocyst survival was not influenced by the incubation time after thawing; however both re-expansion and hatching rates were increased after 20-h incubation. Moreover, the IR per thawed or transferred blastocyst was increased three-fold after 20-h incubation compared to 4-h incubation. Increasing the interval between thawing and transfer appears to be beneficial in order to better select for transfer frozen-thawed blastocysts.

Sperm morphology assessment using David’s classification: time to switch to strict criteria? Prospective comparative analysis in a selected IVF population

The aim of this study was to compare assessment of sperm morphology by using Davids classification (DC), a method of manual analysis most common in France, with a computer-assisted method (Integrated Visual Optical System) based on the strict criteria (CASA SC) for their ability to predict fertilization in a selected in vitro fertilization (IVF) population. A total of 120 couples engaged in IVF protocols were prospectively included in the study. To focus mainly on sperm morphology, couples were excluded in cases of abnormalities of sperm concentration and/or motility and immunological factors and when a low number of oocytes were collected. Sperm morphology analysis was performed on the day of oocyte retrieval by the same trained biologist. Our results showed a moderate correlation between the two techniques (r = 0.49). The DC sperm morphology analysis was less indicative of fertilization than CASA SC (r = 0.07, p = 0.47 vs. r = 0.22, p = 0.014). Using receiver-operating characteristics analysis, we showed that DC was not discriminating in the prediction of fertilization (AUC = 0.572). DC seemed less appropriate for the prediction of fertilization success or failure. In contrast, with CASA SC, the previously determined cut-off value of around 14% was confirmed (AUC = 0.735, cut-off = 6%). Our results argue in favour of the replacement of DC by SC to tend towards worldwide standardization.

Medico-economic approach to the management of uterine myomas: a 6-month cost-effectiveness study of pelvic embolization versus vaginal hysterectomy

INTRODUCTION Uterine artery embolization is a technique that has been recently proposed for the management of uterine myomas an alternative to vaginal hysterectomy. The results provided by the first published studies demonstrate a significant decrease in symptoms in 70-95% of cases. The aim of our study was to compare the cost-effectiveness ratios for pelvic embolization and vaginal hysterectomy looked at from the hospital point of view. MATERIALS AND METHODS Two populations of patients were randomly selected from women undergoing pelvic embolization or vaginal hysterectomy. We retrospectively measured the cost at 6 months of the two types of procedure (costs of hospitalization, drugs, and complementary examinations) as well as the success of each of them at 6 months. The cost of the techniques themselves were measured prospectively on the basis of four procedures. RESULTS The cost-effectiveness ratios were 2320 Euros per success (mean cost 2134 Euros per effectiveness 92%) for embolization and 2789 Euros per success (mean cost 2789 Euros per effectiveness 100%) for hysterectomy. DISCUSSION Pelvic embolization is more cost-effective than vaginal hysterectomy. The integration of the notion of quality of life with the notion of cost should permit a future study to reinforce interest in performing pelvic embolizations in the management of uterine myomas.