Embryo screening: Invasive vs non invasive · Time- lapse imaging Automated non-invasive Duration of 1st cytokinesis Time between end of 1st mitosis and initiation of 2nd Time interval

Embryo screening: Invasive vs non invasive

Joyce HarperJoyce Harper

UCL Centre for PG&D

and CRGH

Institute for Womens Health

University College London

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Overview

• The Omics

• Evidence based medicine

• Invasive screening

• Non invasive screening

• The future


Choosing the best embryo to transferThe Omics

GENOMICS

• genes, chromosomes, mRNA

• (invasive)

PROTEOMICS

• protein secretion

• (non invasive)

METABOLOMICS

• what is secreted or taken up

• (non-invasive)

Do any of these methods help embryo selection and improve delivery rates??


Evidence based medicineWhen and how should new technology be brought into the IVF lab, Harper et al, Human Reproduction , 2011

Assess clinical and cost effectiveness

Tested in larger multi-site clinical study

Tested in small scale single site clinical IVF study

Tested in human embryos donated to research

Hypothesis developed and tested in animal models, including small rodent (mouse) and large animal (bovine and pig)

Hypothesis-driven research, based on many years study of the basic physiology of embryo development


Invasive vs non invasive

• Invasive

– PGS

– Gene expression

• Non invasive

– Analysis of culture media

– Analysis of cumulus

– Analysis of spindles

– Morphology

– Time lapse imaging


Invasive screening

PGS


Gene expression


DNA repair gene expression profilesDNA repair gene expression profilesOocytes compared to blastocystsOocytes compared to blastocysts


Non invasive screening

• Analysis of culture media

• Analysis of cumulus

• Spindle view/birefringence

• Morphology

• Time lapse imaging


Non-invasive assessment of culture media• glucose, lactate, pyruvate, amino acids and factors to evaluate the physiologic and pathologic state of the embryo

• Henry Leese’s ‘quiet embryo’ hypothesis • embryo with ‘quiet’ metabolism has higher viability•‘ active’ metabolism is a stressed embryo

• Renard et al., 1980; Glucose uptake correlated to embryo

• Rieger et al., 1984; Metabolic profile correlated to embryo sex

• Gardner & Leese, 1987; Glucose consumption correlated to blastocyst development


Metabolomics

• Seli et al., 2007; Viability score of 0.31 for implanted embryos and 0.26 for failed implantation (not significant)

• Vergouw et al, 2008; Pilot looking at day 2 and 3, found increased PR

• Seli et al., 2009; Implantation rate 35% in embryos with high viability score and 25% with low score


Array/metabolomics study

Embryo 1

Embryo 4Amplified DNA were analyzed by a-CGH kit (BAC array) from



Amino Acid Profiling

Measuring AA update and release

Leese, Brison, Picton, Sturmey

Picton et al, 2010 showed can predict chromosomally normal embryos

Henry Leese working on EmbryoSure


Analysis of cumulus cells

• Fragouli et al, 2011

• Biomarkers in cumulus

• Still need to determine relevance


Spindle view/birefringence

Shoukir et al, 1997/Madaschi et al, 2008

Oocyte nuclear maturity

birefringent spindles using a light polarisation imaging

Better fertilisation and cleaved earlier

Correlation between zona birefringence

intensity and embryonic implantation potential

(Montag, 2007)


Morphological Assessment

• Istanbul consensus workshop on embryo assessment

• Human Reproduction/RBM Online, 2011

• ESHRE SIG embryology and Alpha


40 hrs hCG 18-20 hrs 42hrs

66 hrs 90 hrs 114-120 hrs

Timeline of Human Embryo Development


Embryo grading


Consensus pointsIstanbul

• Timing key

• Oocyte scoring

• Fertilisation check

• Cleavage embryos

• Morula

• Blastocyst


A B CConclusionsIstanbul

• ‘Omics’ - no routinely applied technique as yet

• Develop embryo scoring system

• Atlas

• Identify best embryos for SET

• External quality assessment

• Importance of time lapse


Time- lapse imaging

Automated non-invasive

Duration of 1st cytokinesisTime between end of 1st mitosis and initiation of 2nd

Time interval between 2nd and 3rd mitosis

More complete picture of embryo than viewing only at a single point in time

Will give important information about embryo development

Will it help embryo selection and increase delivery rates?


Wong et al, 2010Nature Biotechnology

Non invasive imaging of human embryos before embryonic genome activation predicts development to the blastocyst stage

http://www.nature.com/nbt/journal/v28/n10/extref/nbt.1686-S8.mov


Time lapse

• Static vs continuous visualization of embryo development

• No need to take embryo out of incubator

• But – exposure to light

• Humidity


EmbryoscopeData from IVI

• t2, 27 hours post insemination

• t3, 38 hours

• t4, 40 hours

• Key timing is t5

• Blastocysts around 97 hours

• If go straight from 1-3 cells not good

• They grade embryos A-E and exclude them as they fail key milestones


Current status with time lapse

• Only use in ICSI as need to know exact timing of fertilization

• Giving very useful embryology data

• Makes it easier for embryologists

– Especially checking for pronuclei

• But added work load to analyse movies

• Still trying to work out useful parameters

• Several randomised controlled trials going on

• Need to see if it improves delivery rates


Concluding remarksWhich is the best method for embryo selection?

• PGS?

• Analyzing culture media?

• Time lapse?

• Morphology?

• Harper, Magli, Lundin, Barratt, Brison

• When should new technology be introduced into the IVF laboratory?


The Future?The Future?


Documents

Embryo screening: Invasive vs non invasive · Time- lapse imaging Automated non-invasive Duration of 1st cytokinesis Time between end of 1st mitosis and initiation of 2nd Time interval