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Finer points of trophectoderm biopsy using the Saturn 5 laser system - Alpesh Doshi

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A presentation given by Alpesh Doshi, Head of Embryology, Centre for Reproductive and Genetic Health, UK at the Research Instruments Stand at ESHRE 2013.

Finer points of trophectoderm biopsy using the Saturn 5 laser system - Alpesh Doshi

  1. 1. Optimising Trophectoderm Biopsy using the Saturn 5™ Biopsy Mode Alpesh Doshi Centre for Reproductive and Genetic Health. London alpesh.doshi@uclh.nhs.uk
  2. 2. Blastocyst Biopsy • Zona drilling Day 3/4/5 • Biopsy day 5/6 • Differentiation of cell lines occurred – Inner Cell Mass (ICM) – Trophectoderm (TE) • TE herniating through the opening • ~5 cells excised – Glass needle – Laser
  3. 3. Blastocyst Biopsy • Benefits – Larger number of cells can be taken – Smaller proportion of embryonic mass taken – Not taking cells destined to contribute to the foetus • Drawbacks – Short time for diagnosis – <50% Blastocyst formation • Fewer embryos to test • Increased cycle cancellation – High levels of mosaicism • ?Preferential allocation of abnormal cells to TE? – Ethical acceptance
  4. 4. Diagram showing the two approaches for blastocyst biopsy
  5. 5. Hatched Blastocyst Biopsy (Video)
  6. 6. Courtesy Sydney IVF
  7. 7. Courtesy Sydney IVF
  8. 8. When and what to biopsy? WHEN? Take into account how long the diagnosis will take. Vitryfying blastocysts post biopsy? Or aiming for fresh embryo transfer? WHAT? Hatching or Hatched blastocysts. Hatching more ideal If non herniating – trophectoderm cells may have to be ‘sucked’ from zona – ? more risk of lysis and damage to the embryo. Wait. ICM position – wait to d6 if ICM hatching out.
  9. 9. The procedure - Carried out in hepes Buffered media - Procedure has to be rapid. - Minimise laser shots by exerting tension on TE in pipette. - Minimise TE lysis at site of tear. - Use smaller laser pulses (at CRGH 0.377 m/s pulses with Saturn 5) - Collapse cavity first to prevent shoot up of cells in pipette. .
  10. 10. Common difficulties • Positioning of embryo/pipettes (Hatched blastocysts, ICM hatching out) • Do not take too many cells! Remember image is 3D • Control at all times – both holding, suction and laser. Utilise foot pedal if possible
  11. 11. Technique of excising cells  Laser shot and tear cells  Fewer laser shots and ‘brushing’ the cells off using the holding pipette. - Difficulty: Cells are sticky! - more likely to leave cells on holding/aspiration pipette (potential contamination so ensure pipettes changed if necessary) - this technique has to be used for completely hatched blastocysts
  12. 12. TE Biopsy with the new Saturn 5™ Biopsy Mode • Movable laser. • Ability to draw the path to apply laser shots. • Laser shots spaced out to prevent heat build up. • Facilitates process without the need to free hands for repeat laser application. • Prevents application of laser shots at the same point. • Can bend the path to facilitate laser application in curves ie on Zona
  13. 13. Safety of continuous pulses • Laser Pulses spaced 500 milliseconds apart • Heat dissipates within 1 millisecond. • Power of laser 400 MW • Movable laser so will not hit same spot.
  14. 14. Vitrification of biopsied embryos • >80% pregnancy rates with biopsied/vitrified blastocysts post PGS (Schoolcraft &Fragouli 2010 )
  15. 15. Literature
  16. 16. Literature Capalbo et al 2012 • 47.6% of embryos had post zygotic errors detected •20% of aneuploidies detected at PB and D3 corrected at the blastocyst stage
  17. 17. Thank you alpesh.doshi@uclh.nhs.uk

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