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![Limits ? Questions raised ?
• EBM : what about RCTs on embryo morphology ?
• Can morphology criteria be used in all patients ?
– Loss of correlation with implantation with increasing maternal age (Stensen et
al, 2010)
• Can morphology criteria be used in all labs ?
– Developmental speed varies according to culture conditions (media, [O2]…).
Should each laboratory build its own guidelines ?
• Intra and inter observer variability (Paternot et al, 2009; Arce et al, 2006)
• Real or theoretical non invasiveness ?
• No good correlation with genetic content : most embryos with good
morphology are chromosomally abnormal, especially in older women
However, correlations between morphology and implantation remain high,
although not absolute](https://image.slidesharecdn.com/humanembryotransfer-141015065959-conversion-gate01/85/Human-embryo-transfer-14-320.jpg)
![The so-called « invasiveness » (2)
Morphology assessment
• Morphology assessment means dishes
out of the incubator
• pH, osmolarity and temperature
modifications of the culture media each
time the incubator is opened
– Up to 5.6°C variation in microdrops (Kelly PB
et al, 2010)
– 30 min for temperature recovery and 8 min for
[O2] recovery in large incubators
– pH>7.4 in 2 minutes out of the incubator
• Consequences on embryo development
have not been evaluated…](https://image.slidesharecdn.com/humanembryotransfer-141015065959-conversion-gate01/85/Human-embryo-transfer-32-320.jpg)
![Embryo [transfer strategy] selection
• Extended culture to the blastocyst stage is thought to result in
better embryo selection and higher implantation rates.
• BUT … is it suitable for every patients ? For every cycles ?
• Nomogram = statistical tool to generate graphical representation of
a predictive model
• Nomogram used to build a
predictive model of blastocyst
transfer cancellation
(Dessolle, Freour et al, 2010)
• Could help in reducing the
incidence of cancelled Day 5 transfers
• Currently undergoing external
multicenter validation](https://image.slidesharecdn.com/humanembryotransfer-141015065959-conversion-gate01/85/Human-embryo-transfer-38-320.jpg)
![Limits ? Questions raised ?
• EBM : what about RCTs on embryo morphology ?
• Can morphology criteria be used in all patients ?
– Loss of correlation with implantation with increasing maternal age (Stensen et
al, 2010)
• Can morphology criteria be used in all labs ?
– Developmental speed varies according to culture conditions (media, [O2]…).
Should each laboratory build its own guidelines ?
• Intra and inter observer variability (Paternot et al, 2009; Arce et al, 2006)
• Real or theoretical non invasiveness ?
• No good correlation with genetic content : most embryos with good
morphology are chromosomally abnormal, especially in older women
However, correlations between morphology and implantation remain high,
although not absolute](https://image.slidesharecdn.com/humanembryotransfer-141015065959-conversion-gate01/75/Human-embryo-transfer-14-2048.jpg)
![The so-called « invasiveness » (2)
Morphology assessment
• Morphology assessment means dishes
out of the incubator
• pH, osmolarity and temperature
modifications of the culture media each
time the incubator is opened
– Up to 5.6°C variation in microdrops (Kelly PB
et al, 2010)
– 30 min for temperature recovery and 8 min for
[O2] recovery in large incubators
– pH>7.4 in 2 minutes out of the incubator
• Consequences on embryo development
have not been evaluated…](https://image.slidesharecdn.com/humanembryotransfer-141015065959-conversion-gate01/75/Human-embryo-transfer-32-2048.jpg)
![Embryo [transfer strategy] selection
• Extended culture to the blastocyst stage is thought to result in
better embryo selection and higher implantation rates.
• BUT … is it suitable for every patients ? For every cycles ?
• Nomogram = statistical tool to generate graphical representation of
a predictive model
• Nomogram used to build a
predictive model of blastocyst
transfer cancellation
(Dessolle, Freour et al, 2010)
• Could help in reducing the
incidence of cancelled Day 5 transfers
• Currently undergoing external
multicenter validation](https://image.slidesharecdn.com/humanembryotransfer-141015065959-conversion-gate01/75/Human-embryo-transfer-38-2048.jpg)
More Related Content
複製 Human embryo transfer
- 1. Thomas FREOUR Centre d’AssistanceMédicale à la Procréation CHU de Nantes, Nantes, France EMBRYO SELECTION Lyon, September 24th 2010
- 2. Framework 1. Introduction 2. Embryomorphology 3. Genomics 4. Embryo metabolism 5. Debate / Comments
- 3. INTRODUCTION (1) • Increaseuse of ART around the world • Results remain « disappointing » : – Low implantation rate – High multiple pregnancy rate Need for better embryo selection method(s) to improve implantation rates and subsequently lower multiple pregnancy rate.
- 4. INTRODUCTION (2) The literatureavailable Large amount of data from cohort studies, cross sectional studies … But… relatively few studies with a high level of evidence according to evidence-based medicine criteria (RCTs, meta analysis …)
- 5. INTRODUCTION (3) The methodof embryo quality assessment depends on the end-point measure… Cleavage rate Rate of morphologically « top » embryos Blastulation rate Implantation rate Pregnancy rate per transfer Live birth rate per transfer Number of oocytes/embryos necessary to obtain a live birth …
- 6. INTRODUCTION (4) What wouldbe the « ideal » embryo quality assessment method ? « Non invasive » « Do no harm » Reproducible Objective Rapid Easy to use routinely Cost-effective No ethical question raised Independent of other parameters
- 7.
- 8. Embryo morphology : Canyou judge a book by its cover ? Day 0 : Oocyte quality • Nuclear maturity • Cytoplasmic halo or viscosity (Ebner T et al, 2003) • Aggregation of smooth endoplasmic reticulum (Ebner T et al, 2008) • Zona refringence (Montag et al, RBM, 2008) • Spindle position assessment ? (Woodward et al, RBM, 2008)
- 9. Embryo morphology : Canyou judge a book by its cover ? Day 1: zygote • Pronuclei score (Gianaroli et al, FS 2003 & HR 2007, Scott et al, HR, 2000) • Cytoplasmic halo (Ebner T et al, 2003) • Early syngamy (Edgar et al, 2004) • Early cleavage (van Montfoort et al, 2004) • Early cleavage & fragmentation rate (Ferrieres et al, 2007; Hesters et al, 2008)
- 10. Embryo morphology : Canyou judge a book by its cover ? Day 2 or 3 (Ziebe et al, 2003; Moriwaki et al, 2004, Holte et al, 2007; Weitzman et al, 2010; Pelinck et al, 2010…) • Number, size, regularity of blastomeres • Fragmentation • multinucleation • Developmental speed
- 11. Embryo morphology : Canyou judge a book by its cover ? Day 5 (Gardner DK et al, FS, 2000) • Embryoblast / ICM • Trophoblast cells
- 12. Embryo morphology « Noninvasive » ? Reproducible Objective Rapid Easy to use routinely Cost-effective No ethical question raised Independent of other parameters
- 13. Limits of embryomorphology All that glitters is not gold…
- 14. Limits ? Questionsraised ? • EBM : what about RCTs on embryo morphology ? • Can morphology criteria be used in all patients ? – Loss of correlation with implantation with increasing maternal age (Stensen et al, 2010) • Can morphology criteria be used in all labs ? – Developmental speed varies according to culture conditions (media, [O2]…). Should each laboratory build its own guidelines ? • Intra and inter observer variability (Paternot et al, 2009; Arce et al, 2006) • Real or theoretical non invasiveness ? • No good correlation with genetic content : most embryos with good morphology are chromosomally abnormal, especially in older women However, correlations between morphology and implantation remain high, although not absolute
- 15. Time-Lapse Cinematography : thefuture of morphology ? • Principle : dynamic morphometric assessment • allows precise measurement of 1st cleavage time, PN fading … • Prevents from taking the dishes out of the incubator • Can be associated with respirometry Embryoscope ® Primo Vision ®
- 16.
- 17. Genetic content Genomics /Transcriptomics Does a good beginning make a good ending ? Aneuploidy and embryo morphology : most embryos with good morphology are chromosomally abnormal, especially in older women (Magli, Munne 2006) • Need for systematic PGS ?
- 18. PGS • Contradicting PGSresults : most studies reported a positive effect but 2 famous studies reported a detrimental effect of PGD (Mastenbroek NEJM 2007, Hardarson Hum Rep 2008) • Explanations : – Biological : mosaicism, self correction – Technical ++ (misdiagnosis) : arrays, 1 cell biopsy
- 19. PGS How should PGSbe performed to improve pregnancy rates ? – Technical improvement (WGA CGH, SNP array) but ethical concern about unexpected mutations identification – Blastocyst stage biopsy associated with vitrification (Schoolcraft et al, 2010) – Only if a reasonable number of zygotes/embryos available (Munne S, 2010)
- 20. Gamete surroundings Oocyte-cumulus dialogue •Interactions between CCs and oocyte mandatory for oocyte maturation • Transcriptomic profile of cumulus cells has been shown to reflect oocyte competence and subsequent embryo quality and finally implantation potential • Target genes identified, potential biomarkers currently under validation (Assou et al, 2010; Adriaenssens et al, 2010) Assou et al, MHR, 2010
- 21. Genomics « Non invasive» ? Reproducible Objective Rapid Easy to use routinely Cost-effective ? No ethical question raised Independent of other parameters
- 22.
- 23. Embryo metabolism (1) Aminoacids •Early embryo development = intensive metabolic turnover • All AA (essential or not) are necessary for early embryo development (degradation / synthesis cycle) • Correlation with blastocyst development (Houghton et al, 2002) • Correlation with implantation (Brison et al, 2004)
- 24. Embryo metabolism (2) Pyruvateand Glucose • switch from lactate and pyruvate to glucose metabolism around compaction • Pyruvate (<Day 4) and glucose uptake (>Day 4) : – largely studied in the 90’s – Animal models (Gardner DK, 2000) – not proved to be relevant in humans up to now • Association of both could be correlated with blastocystis formation (Gardner et al, 2000, 2001). • Limits : technical aspects, correlation with implantation ? • In the future : technical improvements such as microfluidic chips allowing dynamic metabolioc monitoring (Urbanski, 2008)
- 25. Embryo metabolism (3) Metabolomicanalysis Botros et al, Mol Hum Rep, 2008 • Metabolome : reflects individual embryo phenotype (uptake and release) • Hypothese : differences in metabolism reflect differences in implantation potential • Technics : Near Infra Red (NIR) or RAMAN Spectroscopy • Prediction of embryo viability (and subsequent implantation) according to spectra-based algorithm • Meta analysis confirms correlation with implantation (Botros L et al, 2008)
- 26. Correlation with implantation Independant ofmorphology Independant of the day of assessment • Validated through multicenter blinded studies, RCTs ongoing ? • Commercially available (Viametrics) Embryo metabolism (4) Metabolomic analysis : Viability scores / index (Seli E et al, FS,2009)
- 27. Metabolomic analysis « Noninvasive » Reproducible Objective Rapid Easy to use routinely (extra equipment required) Cost-effective ? No ethical question raised Independent of other parameters (morphology)
- 28. Embryo metabolism (5) Respirometry •Oxygen consumption of preimplantation embryos has been shown to reflect developmental competence and subsequent implantation in animal models (Lopes AS et al, Theriogenelogy, 2007). • Preliminary work on human oocyte with the Embryoscope® (Scott et al, RBMonline, 2008) • No proof of efficiency on human embryos up to now, clinical trials ongoing (Meseguer M et al, IVI)
- 29. Embryo metabolism (6) SecretedFactors • sHLA-G : technical controversy (Sargent et al, 2007) • Follicular IL-15 & GM-CSF (Lédée N et al, FS, 2010)
- 30. 4th Part DEBATE /COMMENTS
- 31. The so-called «invasiveness » (1) « First do no harm » « Primum non nocere » Morphology = « non invasive » ? PGS/PGD = « invasive » ?
- 32. The so-called «invasiveness » (2) Morphology assessment • Morphology assessment means dishes out of the incubator • pH, osmolarity and temperature modifications of the culture media each time the incubator is opened – Up to 5.6°C variation in microdrops (Kelly PB et al, 2010) – 30 min for temperature recovery and 8 min for [O2] recovery in large incubators – pH>7.4 in 2 minutes out of the incubator • Consequences on embryo development have not been evaluated…
- 33. The so-called «invasiveness » (3) PGD/PGS biopsy of 1 cell (De Vos et al, 2010) or trophoblast cells (Schoolcraft et al, 2010) for PGS/ PGD by trained embryologists in a reference laboratory do not affect embryo developmental competence (Munne S et al, 2010)
- 34. Tailored embryo selectioncriteria ? • Women’s age • Ovarian stimulation protocol – Mild vs conventional : benefits still controversial… (Baart EB et al, RBMonline, 2009; Verberg et al, Hum Rep Update, 2009) – Stimulation regimen (Weghofer et al, HR, 2008; Ziebe et al, HR, 2007; Merit Study) : different proportion of euploid embryos, different implantation rates for top quality embryos according to stimulation regimen
- 35. Cost-effectiveness • Must beevaluated on long term and a large scale • In countries where ART cycles are reimbursed, every birth gained yields benefits for the society even in very expensive cases (Evers, IFFS, 2010) • Embryo quality assessment methods must also be evaluated through socio-economical studies
- 36. That means embryoselection is nothing without … Performant embryo freezing program Performant embryo transfer strategy Performant embryo transfer technique Accurate uterine receptivity and timing of embryo transfer
- 37. Performant embryo freezingstrategy ? • Technical restraints : – Vitrification yields significantly higher success rates than slow cooling – Tolerated but not authorized yet in France… • Ethical and/or legal restraints : – Cleavage stage embryo freezing forbidden in Italy
- 38. Embryo [transfer strategy]selection • Extended culture to the blastocyst stage is thought to result in better embryo selection and higher implantation rates. • BUT … is it suitable for every patients ? For every cycles ? • Nomogram = statistical tool to generate graphical representation of a predictive model • Nomogram used to build a predictive model of blastocyst transfer cancellation (Dessolle, Freour et al, 2010) • Could help in reducing the incidence of cancelled Day 5 transfers • Currently undergoing external multicenter validation
- 39. Quality control ofEmbryo transfer • Embryo transfer is an operator- dependent crucial step for achieving pregnancy after IVF • Quality control for learners and for continuous monitoring of performance • Reference = senior gynaecologist • Trainees : 1st : Reach acceptable performance 2nd : maintain adequate level of performance
- 40. In the future… Improvementof the endometrium- embryo dialog ? • COH affects endometrial receptivity (Haouzi et al, Biol Reprod, 2010; Boomsma et al, Fertil Steril, 2010) • Vitrification associated with embryo transfer on spontaneous or hCG-primed natural cycle could result in more physiological endometrial implantation window (Fatemi et al, Fertil Steril, 2010) Haouzi et al, 2010 Boomsma et al, 2010
- 41. What we shouldnot forget …
- 42. Last but notleast… chance, expertise, hazard …?
- 43. Conclusion EMBRYO SELECTION INTHE IVF LAB • It’s a long way from gametogenesis to healthy baby delivery • Improvement in embryo quality assessment method(s) should not result in higher multiple pregnancy rates !! • However, accurate embryo selection in the IVF lab is required but not sufficient to ensure higher implantation rates • The next frontier : select the right embryo for the right endometrium
- 44. Take-Home Message ? •No universally accepted and validated approach, need for customized and individualized methods • Numerous promising technological advances (Omics) • Need for EBM before stopping using morphology
- 45. Thank you foryour attention